section_id,title_number,title_name,chapter,subchapter,part_number,part_name,subpart,subpart_name,section_number,section_heading,agency,authority,source_citation,amendment_citations,full_text 10:10:2.0.1.1.25.0.145.1,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.1 Purpose.,NRC,,,"[56 FR 31504, July 10, 1991]","The regulations in this part set out the annual fees charged to persons who hold licenses, Certificates of Compliance, sealed source and device registrations, and quality assurance program approvals issued by the United States Nuclear Regulatory Commission, including licenses, registrations, approvals, and certificates issued to a Government agency." 10:10:2.0.1.1.25.0.145.10,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,"§ 171.16 Annual fees: Materials licensees, holders of certificates of compliance, holders of sealed source and device registrations, holders of quality assurance program approvals, and government agencies licensed by the NRC.",NRC,,,,"(a)(1) The provisions of this section apply to person(s) who are authorized to conduct activities under— (i) 10 CFR part 30 for byproduct material; (ii) 10 CFR part 40 for source material; (iii) 10 CFR part 70 for special nuclear material; (iv) 10 CFR part 71 for packaging and transportation of radioactive material; and (v) 10 CFR part 76 for uranium enrichment. (2) Notwithstanding the other provisions in this section, the regulations in this part do not apply to uranium recovery and fuel facility licensees until after the Commission verifies through inspection that the facility has been constructed in accordance with the requirements of the license. (3) In accordance with § 171.17, each person identified in paragraph (a)(1) of this section shall pay the applicable annual fee for each license the person holds during the FY. Annual fees will be prorated for new licenses issued and for licenses for which termination is requested and activities permanently ceased during the FY as provided in § 171.17. If a single license authorizes more than one activity (e.g., human use and irradiator activities), annual fees will be assessed for each fee category applicable to the license. If a person holds more than one license, the total annual fee assessed will be the cumulative total of the annual fees applicable to each license held. (b) The FY 2025 annual fee is comprised of a base annual fee and associated additional charges. The base FY 2025 annual fee is the sum of budgeted costs for the following activities: (1) Generic and other research activities directly related to the regulation of materials licenses as defined in this part; and (2) Other safety, environmental, and safeguards activities for materials licenses, except costs for licensing and inspection activities that are recovered under Part 170 of this chapter. (c) A licensee who is required to pay an annual fee under this section, in addition to 10 CFR part 72 licenses, may qualify as a small entity. If a licensee qualifies as a small entity and provides the Commission with the proper certification along with its annual fee payment, the licensee may pay reduced annual fees as shown in table 1 to this paragraph (c). Failure to file a small entity certification in a timely manner could result in the receipt of a delinquent invoice requesting the outstanding balance due and/or denial of any refund that might otherwise be due. The small entity fees are as follows: Table 1 to Paragraph ( c ) (d) The FY 2025 annual fees for materials licensees and holders of certificates, registrations, or approvals subject to fees under this section are shown in table 2 to this paragraph (d): Table 2 to Paragraph ( d )—Schedule of Materials Annual Fees and Fees for Government Agencies Licensed by NRC [See footnotes at end of table] 1 Annual fees will be assessed based on whether a licensee held a valid license with the NRC authorizing possession and use of radioactive material during the current FY. The annual fee is waived for those materials licenses and holders of certificates, registrations, and approvals who either filed for termination of their licenses or approvals or filed for possession only/storage licenses before October 1 of the current FY and permanently ceased licensed activities entirely before this date. Annual fees for licensees who filed for termination of a license, downgrade of a license, or for a possession-only license during the FY and for new licenses issued during the FY will be prorated in accordance with the provisions of § 171.17. If a person holds more than one license, certificate, registration, or approval, the annual fee(s) will be assessed for each license, certificate, registration, or approval held by that person. For licenses that authorize more than one activity on a single license ( e.g., human use and irradiator activities), annual fees will be assessed for each category applicable to the license. 2 Payment of the prescribed annual fee does not automatically renew the license, certificate, registration, or approval for which the fee is paid. Renewal applications must be filed in accordance with the requirements of parts 30, 40, 70, 71, 72, or 76 of this chapter. 3 Each FY, fees for these materials licenses will be calculated and assessed in accordance with § 171.13 and will be published in the Federal Register for notice and comment. 4 Other facilities include licenses for extraction of metals, heavy metals, and rare earths. 5 There are no existing NRC licenses in these fee categories. If NRC issues a license for these categories, the Commission will consider establishing an annual fee for this type of license. 6 Standardized spent fuel facilities, 10 CFR parts 71 and 72 Certificates of Compliance and related Quality Assurance program approvals, and special reviews, such as topical reports, are not assessed an annual fee because the generic costs of regulating these activities are primarily attributable to users of the designs, certificates, and topical reports. 7 Licensees in this category are not assessed an annual fee because they are charged an annual fee in other categories while they are licensed to operate. 8 No annual fee is charged because it is not practical to administer due to the relatively short life or temporary nature of the license. 9 Separate annual fees will not be assessed for pacemaker licenses issued to medical institutions that also hold nuclear medicine licenses under fee categories 7.A, 7.A.1, 7.A.2, 7.B., 7.B.1, 7.B.2, 7.C, 7.C.1, or 7.C.2. 10 This includes Certificates of Compliance issued to the DOE that are not funded from the Nuclear Waste Fund. 11 See § 171.15(c). 12 See § 171.15(c). 13 No annual fee is charged for this category because the cost of the general license registration program applicable to licenses in this category will be recovered through 10 CFR part 170 fees. 14 Persons who possess radium sources that are used for operational purposes in another fee category are not also subject to the fees in this category. (This exception does not apply if the radium sources are possessed for storage only.) 15 Licensees subject to fees under categories 1.A., 1.B., 1.E., 2.A., and licensees paying fees under fee category 17 must pay the largest applicable fee and are not subject to additional fees listed in this table. 16 Licensees paying fees under 3.C. are not subject to fees under 2.B. for possession and shielding authorized on the same license. 17 Licensees paying fees under 7.A, 7.A.1, 7.A.2, 7.B, 7.B.1, 7.B.2, 7.C, 7.C.1, or 7.C.2 are not subject to fees under 2.B. for possession and shielding authorized on the same license. 18 Licensees paying fees under 3.N. are not subject to paying fees under 3.P., 3.P.1, or 3.P.2 for calibration or leak testing services authorized on the same license. 19 Licensees paying fees under 7.B., 7.B.1, or 7.B.2 are not subject to paying fees under 7.C., 7.C.1, or 7.C.2 for broad scope license licenses issued under parts 30, 35, 40, and 70 of this chapter for human use of byproduct material, source material, and/or special nuclear material, except licenses for byproduct material, source material, or special nuclear material in sealed sources contained in teletherapy devices authorized on the same license. 20 No annual fee is charged for a materials license (or part of a materials license) that has transitioned to this fee category because the decommissioning costs will be recovered through 10 CFR part 170 fees, but annual fees may be charged for other activities authorized under the license that are not in decommissioning status. 21 Licensees paying fees under 4.A., 4.B. or 4.C. are not subject to paying fees under 3.N. licenses that authorize services for other licensees authorized on the same license." 10:10:2.0.1.1.25.0.145.11,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.17 Proration.,NRC,,,"[72 FR 31431, June 6, 2007, as amended at 77 FR 35835, June 15, 2012; 83 FR 29657, June 25, 2018; 85 FR 37277, June 19, 2020; 86 FR 32183, June 16, 2021]","Annual fees will be prorated for NRC licensees as follows: (a) Reactors, 10 CFR part 72 licensees who do not hold 10 CFR part 50 or 10 CFR part 52 licenses, and materials licenses with annual fees of $100,000 or greater for a single fee category. The NRC will base the proration of annual fees for terminated and downgraded licenses on the fee rule in effect at the time the action is official. The NRC will base the determinations on the proration requirements under paragraphs (a)(2) and (3) of this section. (1) New licenses. (i) The annual fees for new licenses for power reactors and small modular reactors that are subject to fees under this part, for which the licensee has notified the NRC on or after October 1 of a fiscal year (FY) that the licensee has successfully completed power ascension testing, are prorated on the basis of the number of days remaining in the FY. Thereafter, the full annual fee is due and payable each subsequent FY. (ii) The annual fees for new licenses for non-power production or utilization facilities, 10 CFR part 72 licensees who do not hold 10 CFR part 50 or 52 licenses, and materials licenses with annual fees of $100,000 or greater for a single fee category for the current FY, that are subject to fees under this part and are granted a license to operate on or after October 1 of a FY, are prorated on the basis of the number of days remaining in the FY. Thereafter, the full annual fee is due and payable each subsequent FY. (2) Terminations. The base operating power reactor annual fee for operating reactor licensees or the annual fee for small modular reactor licensees, who have requested amendment to withdraw operating authority permanently during the FY will be prorated based on the number of days during the FY the license was in effect before docketing of the certifications for permanent cessation of operations and permanent removal of fuel from the reactor vessel or when a final legally effective order to permanently cease operations has come into effect. The spent fuel storage/reactor decommissioning annual fee for reactor licensees who permanently cease operations and have permanently removed fuel from the site during the FY will be prorated on the basis of the number of days remaining in the FY after docketing of both the certifications of permanent cessation of operations and permanent removal of fuel from the site. The spent fuel storage/reactor decommissioning annual fee will be prorated for those 10 CFR part 72 licensees who do not hold a 10 CFR part 50 or 52 license who request termination of the 10 CFR part 72 license and permanently cease activities authorized by the license during the FY based on the number of days the license was in effect before receipt of the termination request. The annual fee for materials licenses with annual fees of $100,000 or greater for a single fee category for the current FY will be prorated based on the number of days remaining in the FY when a termination request or a request for a possession-only license is received by the NRC, provided the licensee permanently ceased licensed activities during the specified period. The annual fee for non-power production or utilization facilities will be prorated based on the number of days remaining in the FY when the authorization to operate the facility has been permanently removed from the license during the FY. (3) Downgraded licenses. The annual fee for a materials license with an annual fee of $100,000 or greater for a single fee category for the current FY, that is subject to fees under this part and downgraded on or after October 1 of a FY, is automatically prorated by the agency on the basis of the number of days remaining in the FY when the application for downgrade is received and approved by the NRC, provided the licensee permanently ceased the stated activities during the specified period. (b) Materials licenses (excluding 10 CFR part 72 licenses and materials license with annual fees of $100,000 or greater for a single fee category, included in § 171.17(a)). (1) New licenses. The annual fee for a materials license that is subject to fees under this part and issued on or after October 1 of the FY is prorated on the basis of when the NRC issues the new license. New licenses issued during the period October 1 through March 31 of the FY will be assessed one-half the annual fee for that FY. New licenses issued on or after April 1 of the FY will not be assessed an annual fee for that FY. Thereafter, the full fee is due and payable each subsequent FY. (2) Terminations. The annual fee will be prorated for licenses for which a termination request or a request for a POL has been received on or after October 1 of a FY on the basis of when the application for termination or POL is received by the NRC provided the licensee permanently ceased licensed activities during the specified period. Licenses for which applications for termination or POL are filed during the period October 1 through March 31 of the FY are assessed one-half the annual fee for the applicable category(ies) for that FY. Licenses for which applications for termination or POL are filed on or after April 1 of the FY are assessed the full annual fee for that FY. Materials licenses transferred to a new Agreement State during the FY are considered terminated by the NRC, for annual fee purposes, on the date that the Agreement with the State becomes effective; therefore, the same proration provisions will apply as if the licenses were terminated. (3) Downgraded licenses. (i) The annual fee for a materials license that is subject to fees under this part and downgraded on or after October 1 of a FY is automatically prorated on the basis of the date when the application for downgrade is received and approved by the NRC, provided the licensee permanently ceased the stated activities during the specified period. (ii) Annual fees for licenses for which applications to downgrade are filed during the period October 1 through March 31 of the FY will be prorated as follows: (A) Licenses for which applications have been filed to reduce the scope of the license from a higher fee category(ies) to a lower fee category(ies) will be assessed one-half the annual fee for the higher fee category and one-half the annual fee for the lower fee category(ies), and, if applicable, the full annual fee for fee categories not affected by the downgrade; and (B) Licenses with multiple fee categories for which applications have been filed to downgrade by deleting a fee category will be assessed one-half the annual fee for the fee category being deleted and the full annual fee for the remaining categories. (iii) Licenses for which applications to downgrade are filed on or after April 1 of the FY are assessed the full fee for that FY." 10:10:2.0.1.1.25.0.145.12,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.19 Payment.,NRC,,,"[65 FR 36968, June 12, 2000, as amended at 66 FR 32478, June 14, 2001; 71 FR 30755, May 30, 2006; 71 FR 33190, June 8, 2006; 72 FR 31432, June 6, 2007; 78 FR 39491, July 1, 2013; 79 FR 37154, June 30, 2014; 82 FR 30708, June 30, 2017; 89 FR 51822, June 20, 2024]","(a) Method of payment. All annual fee payments under this part are to be made payable to the U.S. Nuclear Regulatory Commission. The payments are to be made in U.S. funds using the electronic payment methods accepted at www.Pay.gov. Federal agencies may also make payment by IntraGovernmental Payment and Collection (IPAC). Specific instructions for making payments may be obtained by contacting the Office of the Chief Financial Officer at 301-415-7554. In accordance with Department of the Treasury requirements, refunds will only be made upon receipt of information on the payee's financial institution and bank accounts. (b) Annual fees in the amount of $100,000 or more and described in the Federal Register document issued under § 171.13, must be paid in quarterly installments of 25 percent as billed by the NRC. The quarters begin on October 1, January 1, April 1, and July 1 of each fiscal year. The NRC will adjust the fourth quarterly invoice to recover the full amount of the revised annual fee. If the amounts collected in the first three quarters exceed the amount of the revised annual fee, the overpayment will be refunded. Licensees whose annual fee for the previous fiscal year was less than $100,000 (billed on the anniversary date of the license), and whose revised annual fee for the current fiscal year is $100,000 or greater (subject to quarterly billing), will be issued a bill upon publication of the final rule for the full amount of the revised annual fee for the current fiscal year, less any payments received for the current fiscal year based on the anniversary date billing process. (c) Annual fees that are less than $100,000 are billed on the anniversary date of the license. For annual fee purposes, the anniversary date of the license is considered to be the first day of the month in which the original license was issued by the NRC. Licensees that are billed on the license anniversary date will be assessed the annual fee in effect on the anniversary date of the license. Materials licenses subject to the annual fee that are terminated during the fiscal year but before the anniversary month of the license will be billed upon termination for the fee in effect at the time of the billing. New materials licenses subject to the annual fee will be billed in the month the license is issued or in the next available monthly billing for the fee in effect on the anniversary date of the license. Thereafter, annual fees for new licenses will be assessed in the anniversary month of the license. (d) Annual fees of less than $100,000 must be paid as billed by the NRC. Materials license annual fees that are less than $100,000 are billed on the anniversary date of the license. The materials licensees that are billed on the anniversary date of the license are those covered by fee categories 1.C., 1.D., 1.F., and 2.A.(2) through 9.D. (e) Payment is due on the invoice date and interest accrues from the date of the invoice. However, interest will be waived if payment is received within 30 days from the invoice date. (f) The NRC is entitled to collect any underpayment of fees as a result of an error by the NRC." 10:10:2.0.1.1.25.0.145.13,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.21 [Reserved],NRC,,,, 10:10:2.0.1.1.25.0.145.14,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.23 Enforcement.,NRC,,,"[56 FR 31510, July 10, 1991]","If any person required to pay the annual fee fails to pay when the fee is due, or files a false certification with respect to qualifying as a small entity under the Regulatory Flexibility Criteria, the Commission may refuse to process any application submitted by or on behalf of the person with respect to any license issued to the person and may suspend or revoke any licenses held by the person. The filing of a false certification to qualify as a small entity under § 171.16(c) of this part may also result in punitive action pursuant to 18 U.S.C. 1001." 10:10:2.0.1.1.25.0.145.15,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,"§ 171.25 Collection, interest, penalties, and administrative costs.",NRC,,,"[56 FR 31511, July 10, 1991]","All annual fees in §§ 171.15 and 171.16 will be collected pursuant to the procedures of 10 CFR part 15. Interest, penalties and administrative costs for late payments will be assessed in accordance with 10 CFR part 15, of this chapter, 4 CFR part 102, and other relevant regulations of the United States Government, as appropriate. In the event a quarterly installment is not made by the appropriate due date specified in § 171.19, the full fee becomes due and payable, with interest, penalties, and administrative costs of collection calculated from the date that quarterly installment was due." 10:10:2.0.1.1.25.0.145.16,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.26 Right to dispute assessed fees.,NRC,,,"[86 FR 32183, June 16, 2021]",All debtors' disputes of fees assessed must be submitted in accordance with 10 CFR 15.31. 10:10:2.0.1.1.25.0.145.2,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.3 Scope.,NRC,,,"[86 FR 32176, June 16, 2021]","The regulations in this part apply to any person holding an operating license for a non-power production or utilization facility issued under 10 CFR part 50 that has provided notification to the Nuclear Regulatory Commission (NRC) that the licensee has successfully completed startup testing, and to any person holding an operating license for a power reactor or small modular reactor licensed under 10 CFR part 50 or a combined license issued under 10 CFR part 52 that has provided notification to the NRC that the licensee has successfully completed power ascension testing. The regulations in this part also apply to any person holding a materials license as defined in this part, a certificate of compliance, a sealed source or device registration, a quality assurance program approval, and to a Government agency as defined in this part. Notwithstanding the other provisions in this section, the regulations in this part do not apply to uranium recovery and fuel facility licensees until after the Commission verifies through inspection that the facility has been constructed in accordance with the requirements of the license." 10:10:2.0.1.1.25.0.145.3,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.5 Definitions.,NRC,,,"[51 FR 33230, Sept. 18, 1986, as amended at 53 FR 52652, Dec. 29, 1988; 56 FR 31505, July 10, 1991; 57 FR 32714, July 23, 1992; 58 FR 38695, July 20, 1993; 65 FR 36964, June 12, 2000; 66 FR 32474, June 14, 2001; 67 FR 42634, June 24, 2002; 71 FR 30752, May 30, 2006; 72 FR 35936, Oct. 1, 2007; 81 FR 32627, May 24, 2016; 81 FR 45964, July 15, 2016; 83 FR 29652, June 25, 2018; 86 FR 32177, June 16, 2021; 88 FR 39145, June 15, 2023; 89 FR 106253, Dec. 30, 2024]","Budget means the funds appropriated by Congress for the NRC for each fiscal year, and if that appropriation is not passed on or before September 1 for that fiscal year, the funds most recently appropriated by Congress for the most recent fiscal year. Budget authority means the authority, in the form of an appropriation, provided by law and becoming available during the year, to enter into obligations that will result in immediate or future outlays involving Federal Government funds. The appropriation is an authorization by an Act of Congress that permits the NRC to incur obligations and to make payments out of the Treasury for specified purposes. Fees assessed pursuant to Public Law 115-439 are based on the NRC's budget authority. Bundled unit means multiple SMRs on a single site that are considered a single unit for the purpose of assessing an annual fee. A bundled unit is assessed an annual fee based on the cumulative licensed thermal power rating of all licensed SMRs on the same site. The maximum capacity of a bundled unit is a cumulative licensed thermal power rating of 4,500 MWt. A single SMR can be part of two bundled units if it completes the capacity of one unit and begins the capacity of an additional unit. For a given site, the use of the bundled unit concept is independent of the number of SMR plants, the number of SMR licenses issued, or the sequencing of the SMR licenses that have been issued. Bundled units with capacities greater than 2,000 MWt and less than or equal to 4,500 MWt are assessed a maximum fee that is equivalent to the annual fee paid by the current reactor fleet. Above 4,500 MWt establishes an additional bundled unit. Byproduct material means— (1) Any radioactive material (except special nuclear material) yielded in, or made radioactive by, exposure to the radiation incident to the process of producing or using special nuclear material; (2)(i) Any discrete source of radium-226 that is produced, extracted, or converted after extraction, before, on, or after August 8, 2005, for use for a commercial, medical, or research activity; or (ii) Any material that— (A) Has been made radioactive by use of a particle accelerator; and (B) Is produced, extracted, or converted after extraction, before, on, or after August 8, 2005, for use for a commercial, medical, or research activity; and (3) Any discrete source of naturally occurring radioactive material, other than source material, that— (i) The Commission, in consultation with the Administrator of the Environmental Protection Agency, the Secretary of Energy, the Secretary of Homeland Security, and the head of any other appropriate Federal agency, determines would pose a threat similar to the threat posed by a discrete source of radium-226 to the public health and safety or the common defense and security; and (ii) Before, on, or after August 8, 2005, is extracted or converted after extraction for use in a commercial, medical, or research activity. Certificate holder means a person who holds a certificate of compliance, or other package approval issued by the Commission. Commission means the U.S. Nuclear Regulatory Commission or its duly authorized representatives. Federal fiscal year means a year that begins on October 1 of each calendar year and ends on September 30 of the following calendar year. Federal fiscal years are identified by the year in which they end (e.g., fiscal year 1987 begins in 1986 and ends in 1987). Government agency means any executive department, commission, independent establishment, corporation, wholly or partly owned by the United States of America which is an instrumentality of the United States, or any board, bureau, division, service, office, officer, authority, administration, or other establishment in the executive branch of the government. Greater Than Class C Waste or GTCC Waste means low-level radioactive waste that exceeds the concentration limits of radionuclides established for Class C waste in 10 CFR 61.55. High enriched uranium fuel means uranium enriched to 20 percent or greater in the isotope uranium-235. Low enriched uranium fuel means uranium enriched below 20 percent in the isotope uranium-235. Materials license means a license, certificate, approval, registration or other form of permission issued or granted by the NRC under the regulations in 10 CFR parts 30, 31 through 36, 39, 40, 61, 70, 71, 72, and 76. Maximum fee is the highest fee paid by a single bundled unit. It is applied to all bundled units on an SMR site with a licensed thermal power rating greater than 2,000 MWt and less than or equal to 4,500 MWt and is equal to the flat annual fee paid by existing fleet power reactors. Minimum fee means the lowest annual fee assessed for an SMR or a bundled unit in a thermal power rating fee assessment tier. Non-power production or utilization facility means a production or utilization facility licensed under 10 CFR 50.21(a) or (c), or 10 CFR 50.22, as applicable, that is not a nuclear power reactor or production facility as defined under paragraphs (1) and (2) of the definition of “production facility” in 10 CFR 50.2. Nonprofit educational institution means a public or nonprofit educational institution whose primary function is education, whose programs are accredited by a nationally recognized accrediting agency or association, who is legally authorized to provide a program of organized instruction or study, who provides an educational program for which it awards academic degrees, and whose educational programs are available to the public. Nuclear reactor means an apparatus, other than an atomic weapon, used to sustain fission in a self-supporting chain reaction. Operating license means having a license issued pursuant to § 50.57 of this chapter. It does not include licenses that only authorize possession of special nuclear material after the Commission has received a request from the licensee to amend its licensee to permanently withdraw its authority to operate or the Commission has permanently revoked such authority. Person means: (1) Any individual, corporation, partnership, firm, association, trust, estate, public or private institution, group, Government agency other than the Commission; any state or any political subdivision of, or any political entity within, a state; any foreign Government or nation or any political subdivision of any such government or nation; or other entity; and (2) Any legal successor, representative, agent, or agency of the foregoing. Power reactor means a nuclear reactor designed to produce electrical or heat energy and licensed by the Commission under the authority of section 103 or subsection 104b of the Atomic Energy Act of 1954, as amended, and pursuant to the provisions of § 50.21(b) or § 50.22 of this chapter. Quality assurance program approval is the document issued by the NRC to approve the quality assurance program submitted to the NRC as meeting the requirements of § 71.101 of this chapter. Activities covered by the quality assurance program may be divided into two major groups: those activities including design, fabrication and use of packaging and those activities for use only of packaging. Registration holder as used in this part means any manufacturer or initial distributor of a sealed source or device containing a sealed source that holds a certificate of registration issued by the NRC or a holder of a registration for a sealed source or device manufactured in accordance with the unique specifications of, and for use by, a single applicant. Research reactor is defined at 10 CFR 170.3. Small modular reactor (SMR) for the purposes of calculating fees means the class of power reactors having a licensed thermal power rating less than or equal to 1,000 MWt per module. This rating is based on the thermal power equivalent of an SMR with an electrical power generating capacity of 300 MWe or less per module. Small modular reactor site (SMR site) is the geographically bounded location of one or more SMRs and a basis on which SMR fees are calculated. Source material means: (1) Uranium or thorium, or any combination thereof, in any physical or chemical form; or (2) Ores which contain by weight one-twentieth of one percent (0.05%) or more of (i) Uranium, (ii) Thorium, or (iii) Any combination thereof. Source material does not include special nuclear material. Special nuclear material means: (1) Plutonium, uranium-233, uranium enriched in the isotope 233 or in the isotope 235, and any other material which the Commission, pursuant to the provisions of section 51 of the Atomic Energy Act of 1954, as amended, determines to be special nuclear material, but does not include source material; or (2) Any material artificially enriched by any of the foregoing, but does not include source material. Testing facility is defined at 10 CFR 50.2. Variable fee means an annual fee component that is added to the minimum fee. The variable fee is designed to gradually increase as licensed thermal power capacity is added within the bundled unit fee assessment tier. The variable fee is calculated as the product of the incremental increase in the thermal power rating multiplied by the variable rate. Variable rate means the factor used to calculate the variable fee component of the annual fee. To determine the total annual fee, the incremental increase in the licensed thermal power rating within the fee assessment tier is multiplied by the variable rate resulting in a variable fee that is added to the minimum fee. There is a different factor for each SMR or bundled unit fee assessment tier. Each factor represents the difference between the lower licensed thermal power rating within each tier and the actual thermal power rating for the unit or site." 10:10:2.0.1.1.25.0.145.4,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.7 Interpretations.,NRC,,,"[51 FR 33230, Sept. 18, 1986, as amended at 90 FR 55634, Dec. 3, 2025]","Except as specifically authorized by the Commission in writing, no interpretation of the regulations in this part by an officer or employee of the Commission, other than a written interpretation by the General Counsel, will be recognized as binding on the Commission. This section shall cease to have effect on January 8, 2027, unless the NRC determines that the cessation deadline should be extended to a date not more than 5 years in the future after offering the public an opportunity to provide input on the costs and benefits of this section and considering that input. The NRC will publish a document in the Federal Register announcing its determination and revising or removing this section accordingly." 10:10:2.0.1.1.25.0.145.5,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.8 Information collection requirements: OMB approval,NRC,,,"[62 FR 52191, Oct. 6, 1997]",This part contains no information collection requirements and therefore is not subject to the requirements of the Paperwork Reduction Act (44 U.S.C. 3501 et seq. ). 10:10:2.0.1.1.25.0.145.6,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.9 Communications.,NRC,,,"[68 FR 58826, Oct. 10, 2003, as amended at 74 FR 62687, Dec. 1, 2009; 80 FR 74982, Dec. 1, 2015]","All communications concerning the regulations in this part should be addressed to the NRC's Chief Financial Officer, either by mail to the U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; by hand delivery to the NRC's offices at 11555 Rockville Pike, Rockville, Maryland; or, where practicable, by electronic submission, for example, via Electronic Information Exchange, or CD-ROM. Electronic submissions must be made in a manner that enables the NRC to receive, read, authenticate, distribute, and archive the submission, and process and retrieve it a single page at a time. Detailed guidance on making electronic submissions can be obtained by visiting the NRC's Web site at http://www.nrc.gov/site-help/e-submittals.html; by e-mail to MSHD.Resource@nrc.gov; or by writing the Office of the Chief Information Officer, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. The guidance discusses, among other topics, the formats the NRC can accept, the use of electronic signatures, and the treatment of nonpublic information." 10:10:2.0.1.1.25.0.145.7,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.11 Exemptions.,NRC,,,"[56 FR 31505, July 10, 1991, as amended at 57 FR 32714, July 23, 1992; 58 FR 38695, July 20, 1993; 59 FR 12543, Mar. 17, 1994; 59 FR 36924, July 20, 1994; 67 FR 42634, June 24, 2002; 70 FR 30548, May 29, 2005; 79 FR 37150, June 30, 2014; 86 FR 32177, June 16, 2021]","(a) All requests for exemptions must be filed with the NRC within 90 days from the effective date of the final rule establishing the annual fees for which the exemption is sought in order to be considered. Absent extraordinary circumstances, any exemption requests filed beyond that date will not be considered. The filing of an exemption request does not extend the date on which the bill is payable. Only timely payment in full ensures avoidance of interest and penalty charges. If a partial or full exemption is granted, any overpayment will be refunded. Requests for clarification of or questions relating to an annual fee bill must also be filed within 90 days from the date of the initial invoice to be considered. (b) An annual fee is not required for: (1) A construction permit or license applied for by, or issued to, a nonprofit educational institution for a production or utilization facility, other than a power reactor, or for the possession and use of byproduct material, source material, or special nuclear material. This exemption does not apply to those byproduct, source, or special nuclear material licenses which authorize: (i) Human use; (ii) Remunerated services to other persons; (iii) Distribution of byproduct material, source material, or special nuclear material or products containing byproduct material, source material, or special nuclear material; or (iv) Activities performed under a Government contract. (2) Federally-owned and State-owned research reactors used primarily for educational training and academic research purposes. For purposes of this exemption, the term research reactor means a nuclear reactor that— (i) Is licensed by the Nuclear Regulatory Commission under section 104c. of the Atomic Energy Act of 1954 (42 U.S.C. 2134(c)) for operation at a thermal power level of 10 megawatts or less; and (ii) If so licensed for operation at a thermal power level of more than 1 megawatt, does not contain— (A) A circulating loop through the core in which the licensee conducts fuel experiments; (B) A liquid fuel loading; or (C) An experimental facility in the core in excess of 16 square inches in cross-section. (c) The Commission may, upon application by an interested person or on its own initiative, grant an exemption from the requirements of this part that it determines is authorized by law and otherwise in the public interest. (d) An exemption for reactors licensed to operate may be granted by the Commission taking into consideration each of the following factors: (1) Age of the reactor; (2) Number of customers in rate base; (3) Net increase in KWh cost for each customer directly related to the annual fee assessed under this part; and (4) Any other relevant matter which the licensee believes justifies the reduction of the annual fee. (e) The Commission may grant a materials licensee an exemption from the annual fee if it determines that the annual fee is not based on a fair and equitable allocation of the NRC costs. The following factors must be fulfilled as determined by the Commission for an exemption to be granted: (1) There are data specifically indicating that the assessment of the annual fee will result in a significantly disproportionate allocation of costs to the licensee, or class of licensees; or (2) There is clear and convincing evidence that the budgeted generic costs attributable to the class of licensees are neither directly or indirectly related to the specific class of licensee nor explicitly allocated to the licensee by Commission policy decisions; or (3) Any other relevant matter that the licensee believes shows that the annual fee was not based on a fair and equitable allocation of NRC costs." 10:10:2.0.1.1.25.0.145.8,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,§ 171.13 Notice.,NRC,,,"[64 FR 31475, June 10, 1999]","The annual fees applicable to any NRC licensee subject to this part and calculated in accordance with §§ 171.15 and 171.16, will be published as a notice in the Federal Register as soon as possible but no later than the third quarter of the fiscal year. The annual fees will become due and payable to the NRC as indicated in § 171.19. Quarterly payments of the annual fee of $100,000 or more will continue during the fiscal year and be based on the applicable annual fees as shown in §§ 171.15 and 171.16 until a notice concerning the revised amount of the fees for the fiscal year is published by the NRC. If the NRC is unable to publish a final fee rule that becomes effective during the current fiscal year, fees would be assessed based on the rates in effect for the previous fiscal year." 10:10:2.0.1.1.25.0.145.9,10,Energy,I,,171,"PART 171—ANNUAL FEES FOR REACTOR LICENSES AND FUEL CYCLE LICENSES AND MATERIALS LICENSES, INCLUDING HOLDERS OF CERTIFICATES OF COMPLIANCE, REGISTRATIONS, AND QUALITY ASSURANCE PROGRAM APPROVALS AND GOVERNMENT AGENCIES LICENSED BY THE NRC",,,,"§ 171.15 Annual fees: Non-power production or utilization licenses, reactor licenses, and independent spent fuel storage licenses.",NRC,,,"[72 FR 31426, June 6, 2007, as amended at 72 FR 49566, Aug. 28, 2007; 73 FR 32407, June 6, 2008; 74 FR 27665, June 10, 2009; 75 FR 34240, June 16, 2010; 76 FR 36802, June 22, 2011; 77 FR 35831, June 15, 2012; 78 FR 39487, July 1, 2013; 79 FR 37150, June 30, 2014; 80 FR 37460, June 30, 2015; 81 FR 32628, May 24, 2016; 81 FR 45964, July 15, 2016; 81 FR 41192, June 24, 2016; 82 FR 30704, June 30, 2017; 83 FR 29652, June 25, 2018; 84 FR 22356, May 17, 2019; 85 FR 37277, June 19, 2020; 86 FR 32177, June 16, 2021; 87 FR 37221, June 22, 2022; 88 FR 39146, June 15, 2023; 89 FR 51816, June 20, 2024; 90 FR 26759, June 24, 2025]","(a) Each person holding an operating license for one or more non-power production or utilization facilities under 10 CFR part 50 that has provided notification to the NRC of the successful completion of startup testing; each person holding an operating license for a power reactor licensed under 10 CFR part 50 or a combined license under 10 CFR part 52 that has provided notification to the NRC of the successful completion of power ascension testing; each person holding a 10 CFR part 50 or 52 power reactor license that is in decommissioning or possession only status, except those that have no spent fuel onsite; and each person holding a 10 CFR part 72 license who does not hold a 10 CFR part 50 or 52 license and provides notification in accordance with 10 CFR 72.80(g), shall pay the annual fee for each license held during the Federal fiscal year in which the fee is due. This paragraph (a) does not apply to test or research reactors exempted under § 171.11(b). (b)(1) The FY 2025 annual fee for each operating power reactor that must be collected by September 30, 2025, is $5,319,000. (2) The FY 2025 annual fees are comprised of a base annual fee for power reactors licensed to operate, a base spent fuel storage/reactor decommissioning annual fee and associated additional charges. The activities comprising the spent fuel storage/reactor decommissioning base annual fee are shown in paragraphs (c)(2)(i) and (ii) of this section. The activities comprising the FY 2025 base annual fee for operating power reactors are as follows: (i) Power reactor safety and safeguards regulation except licensing and inspection activities recovered under part 170 of this chapter and generic reactor decommissioning activities. (ii) Research activities directly related to the regulation of power reactors, except those activities specifically related to reactor decommissioning. (iii) Generic activities required largely for NRC to regulate power reactors (e.g., updating part 50 or 52 of this chapter, operating the Incident Response Center, new reactor regulatory infrastructure). The base annual fee for operating power reactors does not include generic activities specifically related to reactor decommissioning. (c)(1) The FY 2025 annual fee for each power reactor holding a 10 CFR part 50 license or combined license issued under 10 CFR part 52 that is in a decommissioning or possession-only status and has spent fuel onsite, and for each independent spent fuel storage 10 CFR part 72 licensee who does not hold a 10 CFR part 50 license or a 10 CFR part 52 combined license, is $326,000. (2) The FY 2025 annual fee is comprised of a base spent fuel storage/reactor decommissioning annual fee (which is also included in the operating power reactor annual fee shown in paragraph (b) of this section). The activities comprising the FY 2025 spent fuel storage/reactor decommissioning rebaselined annual fee are: (i) Generic and other research activities directly related to reactor decommissioning and spent fuel storage; and (ii) Other safety, environmental, and safeguards activities related to reactor decommissioning and spent fuel storage, except costs for licensing and inspection activities that are recovered under part 170 of this chapter. (d)(1) Each person holding an operating license for an SMR issued under 10 CFR part 50 or a combined license issued under 10 CFR part 52 that has provided notification to the NRC of the successful completion startup testing, shall pay the annual fee for all licenses held for an SMR site. The annual fee will be determined using the cumulative licensed thermal power rating of all SMR units and the bundled unit concept, during the fiscal year in which the fee is due. For a given site, the use of the bundled unit concept is independent of the number of SMR plants, the number of SMR licenses issued, or the sequencing of the SMR licenses that have been issued. (2) The annual fees for a small modular reactor(s) located on a single site to be collected by September 30 of each year, are as follows: Table 1 to Paragraph ( d )(2) a Annual fee paid by the non-power production or utilization facilities fee class. b Average of the annual fees for the spent fuel storage/reactor decommissioning and the non-power production or utilization facilities fee classes. c Annual fee paid by the operating power reactors fee class. d [((b)−(a))/230] × the difference between 20 MWt for the first bundled unit(s) and the actual cumulative licensed thermal power rating up to 250 MWt. e [((c)−(b))/1,750] × the difference between 250 MWt for the first bundled unit(s) and the actual cumulative licensed thermal power rating up to 2,000 MWt. f [((c)−(b))/2,000] × the difference between 4,500 MWt for the first bundled unit(s) and the total actual cumulative licensed thermal power rating up to 2,000 MWt. (3) The annual fee for an SMR collected under this paragraph (d) is in lieu of any fee otherwise required under paragraph (b) of this section. The annual fee under this paragraph (d) covers the same activities listed for the power reactor base annual fee and the spent fuel storage/reactor decommissioning reactor fee. (e) The FY 2025 annual fee for licensees authorized to operate one or more non-power production or utilization facilities under a single 10 CFR part 50 license, unless the reactor is exempted from fees under § 171.11(b), is $96,800." 14:14:3.0.1.4.33.1.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.1 Scope.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-2, 31 FR 5408, Apr. 6, 1966; Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]",This subpart sets forth minimum requirements for the approval and operation on non-Federal VOR facilities that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. 14:14:3.0.1.4.33.1.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.3 Requests for IFR procedure.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]","(a) Each person who requests an IFR procedure based on a VOR facility that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of § 171.7 and is installed in accordance with § 171.9. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and maintenance manual that meets the requirements of § 171.11. (4) A statement of intention to meet the requirements of this subpart. (5) A showing that the facility has an acceptable level of operational reliability and an acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this paragraph. (b) After the FAA inspects and evaluates the facility, it advises the owner of the results and of any required changes in the facility or the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the facility for an in-service evaluation by the FAA." 14:14:3.0.1.4.33.1.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.5 Minimum requirements for approval.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-6, 35 FR 10288, June 24, 1970]","(a) The following are the minimum requirements that must be met before the FAA will approve an IFR procedure for a non-Federal VOR: (1) The facility's performance, as determined by air and ground inspection, must meet the requirements of § 171.7. (2) The installation of the equipment must meet the requirements of § 171.9. (3) The owner must agree to operate and maintain the facility in accord- ance with § 171.11. (4) The owner must agree to furnish periodic reports, as set forth in § 171.13, and must agree to allow the FAA to inspect the facility and its operation whenever necessary. (5) The owner must assure the FAA that he will not withdraw the facility from service without the permission of the FAA. (6) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspections made before the facility is commissioned, except that the Federal Aviation Administration may bear certain of these costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the FAA commissions the facility as a prerequisite to its approval for use in an IFR procedure. The approval is withdrawn at any time the facility does not continue to meet those requirements." 14:14:3.0.1.4.33.1.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.7 Performance requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-7, 35 FR 12711, Aug. 11, 1970; Amdt. 171-9, 38 FR 28557, Oct. 15, 1973]","(a) The VOR must perform in accordance with the “International Standards and Recommended Practices, Aeronautical Telecommunications,” Part I, paragraph 3.3 (Annex 10 to the Convention on International Civil Aviation), except that part of paragraph 3.3.2.1 specifying a radio frequency tolerance of 0.005 percent, and that part of paragraph 3.3.7 requiring removal of only the bearing information. In place thereof, the frequency tolerance of the radio frequency carrier must not exceed plus or minus 0.002 percent, and all radiation must be removed during the specified deviations from established conditions and during periods of monitor failure. (b) Ground inspection consists of an examination of the design features of the equipment to determine that there will not be conditions that will allow unsafe operations because of component failure or deterioration. (c) The monitor is checked periodi- cally, during the in-service test evaluation period, for calibration and stability The tests are made with a standard “Reference and variable phase signal generator” and associated test equipment, including an oscilloscope and portable field detector. In general, the ground check is conducted in accord- ance with section 8.4 of FAA Handbook AF P 6790.9 “Maintenance Instruction for VHF Omniranges”, adapted for the facility concerned. (d) Flight tests to determine the facility's adequacy for operational requirements and compliance with applicable “Standards and Recommended Practices” are conducted in accordance with the “U.S. Standard Flight Inspection Manual”, particularly section 201. (e) After January 1, 1975, the owner of the VOR shall modify the facility to perform in accordance with paragraph 3.3.5.7 of Annex 10 to the Convention on International Civil Aviation within 180 days after receipt of notice from the Administrator that 50 kHz channel spacing is to be implemented in the area and that a requirement exists for suppression of 9960 Hz subcarrier harmonics." 14:14:3.0.1.4.33.1.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.9 Installation requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-7, 35 FR 12711, Aug. 11, 1970; Amdt. 171-16, 56 FR 65664, Dec. 17, 1991]","(a) The facility must be installed according to accepted good engineering practices, applicable electric and safety codes, and the installation must meet at least the Federal Communication Commission's licensing requirements. (b) The facility must have a reliable source of suitable primary power, either from a power distribution system or locally generated, with a supplemental standby system, if needed. (c) Dual transmitting equipment with automatic changeover is preferred and may be required to support certain IFR procedures. (d) There must be a means for determining, from the ground, the performance of the equipment, including the antenna, initially and periodically. (e) A facility intended for use as an instrument approach aid for an airport must have or be supplemented by (depending on circumstances) the following ground-air or landline communications services: (1) At facilities outside of and not immediately adjacent to controlled airspace, there must be ground-air communications from the airport served by the facility. Separate communications channels are acceptable. (2) At facilities within or immediately adjacent to controlled airspace, there must be the ground-air communications required by paragraph (e)(1) of this section and reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communication facility. Paragraphs (e) (1) and (2) of this section are not mandatory at airports where an adjacent FAA facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace and where extensive delays are not a factor, the requirements of paragraphs (e) (1) and (2) of this section may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communication facility, if an adjacent FAA facility can communicate with aircraft during the proposed instrument approach procedure, at least down to the minimum en route altitude for the controlled airspace area." 14:14:3.0.1.4.33.1.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.11 Maintenance and operations requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-2, 31 FR 5408, Apr. 6, 1966]","(a) The owner of the facility must establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility must meet at least the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility including proficiency in maintenance procedures and the use of specialized test equipment. (b) The owner must prepare, and obtain FAA approval of, an operations and maintenance manual that sets forth mandatory procedures for operations, preventive maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons only. (3) FCC licensing requirements for operating and maintenance personnel. (4) Posting of licenses and signs. (5) Relations between the facility and FAA air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information (if applicable), and instructions for the operation of an air traffic advisory service if the VOR is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed and specific maintenance procedures and servicing guides stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of FAA manuals by reference. (9) Keeping of station logs and other technical reports, and the submission of reports required by § 171.13. (10) Monitoring of the facility. (11) Inspections by United States personnel. (12) Names, addresses, and telephone numbers of persons to be notified in an emergency. (13) Shutdowns for routine maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns (private use facilities may omit the “Notices to Airmen”). (14) An explanation of the kinds of activity (such as construction or grading) in the vicinity of the facility that may require shutdown or recertification of the facility by FAA flight check. (15) Procedures for conducting a ground check of course accuracy. (16) Commissioning of the facility. (17) An acceptable procedure for amending or revising the manual. (18) The following information concerning the facility: (i) Location by latitude and longitude to the nearest second, and its position with respect to airport layouts. (ii) The type, make, and model of the basic radio equipment that will provide the service. (iii) The station power emission and frequency. (iv) The hours of operation. (v) Station identification call letters and method of station identification, whether by Morse code or recorded voice announcement, and the time spacing of the identification. (vi) A description of the critical parts that may not be changed, adjusted, or repaired without an FAA flight check to confirm published operations. (c) The owner shall make a ground check of course accuracy each month in accordance with procedures approved by the FAA at the time of commissioning, and shall report the results of the checks as provided in § 171.13. (d) If the owner desires to modify the facility, he must submit the proposal to the FAA and may not allow any modifications to be made without specific approval. (e) The owner's maintenance personnel must participate in initial inspections made by the FAA. In the case of subsequent inspections, the owner or his representative shall participate. (f) Whenever it is required by the FAA, the owner shall incorporate improvements in VOR maintenance brought about by progress in the state of the art. In addition, he shall provide a stock of spare parts, including vacuum tubes, of such a quantity to make possible the prompt replacement of components that fail or deteriorate in service. (g) The owner shall provide all approved test instruments needed for maintenance of the facility. (h) The owner shall close the facility upon receiving two successive pilot reports of its malfunctioning." 14:14:3.0.1.4.33.1.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,A,Subpart A—VOR Facilities,,§ 171.13 Reports.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-5, 34 FR 15245, Sept. 30, 1969; Amdt. 171-10, 40 FR 36110, Aug. 19, 1975]","The owner of each facility to which this subpart applies shall make the following reports on forms furnished by the FAA, at the times indicated, to the FAA Regional office for the area in which the facility is located: (a) Record of meter readings and adjustments ( Form FAA-198 ). To be filled out by the owner with the equipment adjustments and meter readings as of the time of commissioning, with one copy to be kept in the permanent records of the facility and two copies to the appropriate Regional office of the FAA. The owner shall revise the form after any major repair, modernization, or returning, to reflect an accurate record of facility operation and adjustment. (b) Facility maintenance log ( FAA Form 6003-1 ). This form is a permanent record of all equipment malfunctioning met in maintaining the facility, including information on the kind of work and adjustments made, equipment failures, causes (if determined), and corrective action taken. The owner shall keep the original of each report at the facility and send a copy to the appropriate Regional office of the FAA at the end of the month in which it is prepared. (c) Radio equipment operation record ( Form FAA-418 ). To contain a complete record of meter readings, recorded on each scheduled visit to the facility. The owner shall keep the original of each month's record at the facility and send a copy of it to the appropriate Regional office of the FAA. (d) [Reserved] (e) VOR ground check error data ( Forms FAA-2396 and 2397 ). To contain results of the monthly course accuracy ground check in accordance with FAA Handbook AF P 6790.9 “Maintenance Instructions for VHF Omniranges”. The owner shall keep the originals in the facility and send a copy of each form to the appropriate Regional office of the FAA on a monthly basis." 14:14:3.0.1.4.33.10.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.301 Scope.,FAA,,,,"This subpart sets forth minimum requirements for the approval, installation, operation and maintenance of non-Federal Microwave Landing System (MLS) facilities that provide the basis for instrument flight rules (IFR) and air traffic control procedures." 14:14:3.0.1.4.33.10.3.10,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.319 Approach elevation monitor system requirements.,FAA,,,,"(a) The monitor system must act to ensure that any of the following conditions do not persist for longer than the periods specified when: (1) There is a change in the ground component contribution to the mean glidepath error component such that the path following error on any glidepath exceeds the limits specified in § 171.317(d) for a period of more than one second. The above requirement and the requirement to limit the ground equipment mean error to ±0.067 degree can be satisfied by the following procedure. The integral monitor alarm limit should be set to ±0.067 degree. This will limit the electrical component of mean glidepath error to ±0.067 degree. The field monitor alarm limit should be set such that with the mean glidepath error at the alarm limit the total allowed PFE is not exceeded on any commissioned glidepath from the limit of coverage to an altitude of 100 feet. (2) There is a reduction in the radiated power to a level not less than that specified in § 171.317(a)(4) for a period of more than one second. (3) There is an error in the preamble DPSK transmission which occurs more than once in any one second period. (4) There is an error in the time division multiplex synchronization of a particular elevation function such that the requirement specified in § 171.311(e) is not satisfied and this condition persists for more than one second. (5) A failure of the monitor is detected. (b) The period during which erroneous guidance information is radiated must not exceed the periods specified in § 171.319(a). If the fault is not cleared within the time allowed, radiation shall cease. After shutdown, no attempt must be made to restore service until a period of 20 seconds has elapsed." 14:14:3.0.1.4.33.10.3.11,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.321 DME and marker beacon performance requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended at 69 FR 18803, Apr. 9, 2004]","(a) The DME equipment must meet the performance requirements prescribed in subpart G of the part. This subpart imposes requirements that performance features must comply with International Standards and Recommended Practices, Aeronautical Telecommunications, Vol. I of Annex 10 to ICAO. It is available from ICAO, Aviation Building, 1080 University Street, Montreal 101, Quebec, Canada, Attention: Distribution Officer and also available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. (b) MLS marker beacon equipment must meet the performance requirements prescribed in subpart H of this part. This subpart imposes requirements that performance features must comply with International Standards and Recommended Practices, Aeronautical Telecommuncations, Vol. I of Annex 10 to ICAO." 14:14:3.0.1.4.33.10.3.12,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.323 Fabrication and installation requirements.,FAA,,,"[Docket 20669, 51 FR 33177, Sept. 18, 1986, as amended by Amdt. 171-16, 56 FR 65665, Dec. 17, 1991]","(a) The MLS facility must be permanent and must be located, constructed, and installed in accordance with best commercial engineering practices, using applicable electric and safety codes and Federal Communications Commission (FCC) licensing requirements and siting requirements of §§ 171.313(b) and 171.317(b). (b) The MLS facility components must utilize solid state technology except that traveling wave tube amplifiers (TWTA) may be used. A maximum level of common modularity must be provided along with diagnostics to facilitate maintenance and troubleshooting. (c) An approved monitoring capability must be provided which indicates the status of the equipment at the site and at a remotely located maintenance area, with monitor capability that provides pre-alarm of impending system failures. This monitoring feature must be capable of transmitting the status and pre-alarm over standard phone lines to a remote section. In the event the sponsor requests the FAA to assume ownership of the facility, the monitoring feature must also be capable of interfacing with FAA remote monitoring requirements. This requirement may be complied with by the addition of optional software and/or hardware in space provided in the original equipment. (d) The mean corrective maintenance time of the MLS equipment must be equal to or less than 0.5 hours with a maximum corrective maintenance time not to exceed 1.5 hours. This measure applies to correction of unscheduled failures of the monitor, transmitter and associated antenna assemblies, limited to unscheduled outage and out of tolerance conditions. (e) The mean-time-between-failures of the MLS angle system must not be less than 1,500 hours. This measure applies to unscheduled outage, out-of-tolerance conditions, and failures of the monitor, transmitter, and associated antenna assemblies. (f) The MLS facility must have a reliable source of suitable primary power, either from a power distribution system or locally generated. Adequate power capacity must be provided for the operation of the MLS as well as the test and working equipment of the MLS. (g) The MLS facility must have a continuously engaged or floating battery power source for the continued normal operation of the ground station operation if the primary power fails. A trickle charge must be supplied to recharge the batteries during the period of available primary power. Upon loss and subsequent restoration of power, the battery must be restored to full charge within 24 hours. When primary power is applied, the state of the battery charge must not affect the operation of the MLS ground station. The battery must allow continuation of normal operation of the MLS facility for at least 2 hours without the use of additional sources of power. When the system is operating from the battery supply without prime power, the radome deicers and the environmental system need not operate. The equipment must meet all specification requirements with or without batteries installed. (h) There must be a means for determining, from the ground, the performance of the system including antenna, both initially and periodically. (i) The facility must have, or be supplemented by, ground, air, or landline communications services. At facilities within or immediately adjacent to controlled airspace, that are intended for use as instrument approach aids for an airport, there must be ground air communications or reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communication facility. Compliance with this paragraph need not be shown at airports where an adjacent FAA facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of this paragraph may be reduced to reliable communications from the airport to the nearest FAA air traffic control or communications facility. If the adjacent FAA facility can communicate with aircraft during the proposed instrument approach procedure down to the airport surface or at least down to the minimum en route altitude, this would require at least a landline telephone. (j) The location of the phase center for all antennas must be clearly marked on the antenna enclosures. (k) The latitude, longitude and mean sea level elevation of all MLS antennas, runway threshold and runway stop end must be determined by survey with an accuracy of ±3 meters (±10 feet) laterally and ±0.3 meter (±1.0 foot) vertically. The relative lateral and vertical offsets of all antenna phase centers, and both runway ends must be determined with an accuracy of ±0.3 meter (±1.0 foot) laterally and ±0.03 meter (±0.1 foot) vertically. The owner must bear all costs of the survey. The results of this survey must be included in the “operations and maintenance” manual required by section 171.325 of this subpart and will be noted on FAA Form 198 required by § 171.327." 14:14:3.0.1.4.33.10.3.13,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.325 Maintenance and operations requirements.,FAA,,,,"(a) The owner of the facility must establish an adequate maintenance system and provide MLS qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility must meet the FCC licensing requirements and demonstrate that he has the special knowledge and skills needed to maintain an MLS facility, including proficiency in maintenance procedures and the use of specialized test equipment. (b) In the event of out-of-tolerance conditions or malfunctions, as evidenced by receiving two successive pilot reports, the owner must close the facility by encasing radiation, and issue a “Notice to Airmen” (NOTAM) that the facility is out of service. (c) The owner must prepare, and obtain approval of, an operations and maintenance manual that sets forth mandatory procedures for operations, periodic maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons. (3) FCC licensing requirements for operations and maintenance personnel. (4) Posting of licenses and signs. (5) Relations between the facility and FAA air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information, if applicable, and instructions for the operation of an air traffic advisory service if the facility is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed and specific maintenance procedures and servicing guides stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of FAA manuals by reference. (9) Keeping the station logs and other technical reports, and the submission of reports required by § 171.327. (10) Monitoring of the MLS facility. (11) Inspections by United States personnel. (12) Names, addresses, and telephone numbers of persons to be notified in an emergency. (13) Shutdowns for periodic maintenance and issuing of NOTAM for routine or emergency shutdowns. (14) Commissioning of the MLS facility. (15) An acceptable procedure for amending or revising the manual. (16) An explanation of the kinds of activities (such as construction or grading) in the vicinity of the MLS facility that may require shutdown or recertification of the MLS facility by FAA flight check. (17) Procedures for conducting a ground check of the azimuth and elevation alignment. (18) The following information concerning the MLS facility: (i) Facility component locations with respect to airport layout, instrument runways, and similar areas. (ii) The type, make and model of the basic radio equipment that provides the service including required test equipment. (iii) The station power emission, channel, and frequency of the azimuth, elevation, DME, marker beacon, and associated compass locators, if any. (iv) The hours of operation. (v) Station identification call letters and method of station identification and the time spacing of the identification. (vi) A description of the critical parts that may not be changed, adjusted, or repaired without an FAA flight check to confirm published operations. (d) The owner or his maintenance representative must make a ground check of the MLS facility periodically in accordance with procedures approved by the FAA at the time of commissioning, and must report the results of the checks as provided in § 171.327. (e) The only modifications permitted are those that are submitted to FAA for approval by the MLS equipment manufacturer. The owner or sponsor of the facility must incorporate these modifications in the MLS equipment. Associated changes must also be made to the operations and maintenance manual required in paragraph (c) of this section. This and all other corrections and additions to this operations and maintenance manual must also be submitted to FAA for approval. (f) The owner or the owner's maintenance representative must participate in inspections made by the FAA. (g) The owner must ensure the availability of a sufficient stock of spare parts, including solid state components, or modules to make possible the prompt replacement of components or modules that fail or deteriorate in service. (h) FAA approved test instruments must be used for maintenance of the MLS facility. (i) Inspection consists of an examination of the MLS equipment to ensure that unsafe operating conditions do not exist. (j) Monitoring of the MLS radiated signal must ensure a high degree of integrity and minimize the requirements for ground and flight inspection. The monitor must be checked daily during the in-service test evaluation period (96 hour burn in) for calibration and stability. These tests and ground checks or azimuth, elevation, DME, and marker beacon radiation characteristics must be conducted in accordance with the maintenance requirements of this section." 14:14:3.0.1.4.33.10.3.14,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.327 Operational records.,FAA,,,,"The owner of the MLS facility or his maintenance representative must submit the following operational records at the indicated time to the appropriate FAA regional office where the facility is located. (a) Facility Equipment Performance & Adjustment Data (FAA Form 198). The FAA Form 198 shall be filled out by the owner or his maintenance representative with the equipment adjustments and meter readings as of the time of facility commissioning. One copy must be kept in the permanent records of the facility and two copies must be sent to the appropriate FAA regional office. The owner or his maintenance representative must revise the FAA Form 198 data after any major repair, modernization, or retuning to reflect an accurate record of facility operation and adjustment. (b) Facility Maintenance Log (FAA Form 6030-1). FAA Form 6030-1 is permanent record of all the activities required to maintain the MLS facility. The entries must include all malfunctions met in maintaining the facility including information on the kind of work and adjustments made, equipment failures, causes (if determined) and corrective action taken. In addition, the entries must include completion of periodic maintenance required to maintain the facility. The owner or his maintenance representative must keep the original of each form at the facility and send a copy to the appropriate FAA regional office at the end of each month in which it is prepared. However, where an FAA approved remote monitoring system is installed which precludes the need for periodic maintenance visits to the facility, monthly reports from the remote monitoring system control point must be forwarded to the appropriate FAA regional office, and a hard copy retained at the control point. (c) Technical Performance Record (FAA Form 6830 (formerly FAA Form 418)). This form contains a record of system parameters as specified in the manufacturer's equipment manual. This data will be recorded on each scheduled visit to the facility. The owner or his maintenance representative shall keep the original of each record at the facility and send a copy of the form to the appropriate FAA regional office." 14:14:3.0.1.4.33.10.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.303 Definitions.,FAA,,,,"As used in this subpart: Auxiliary data means data transmitted in addition to basic data that provide ground equipment siting information for use in refining airborne position calculations and other supplementary information. Basic data means data transmitted by the ground equipment that are associated directly with the operation of the landing guidance system. Beam center means the midpoint between the −3 dB points on the leading and trailing edges of the scanning beam main lobe. Beamwidth means the width of the scanning beam main lobe measured at the −3 dB points and defined in angular units on the boresight, in the horizontal plane for the azimuth function and in the vertical plane for the elevation function. Clearance guidance sector means the volume of airspace, inside the coverage sector, within which the azimuth guidance information provided is not proportional to the angular displacement of the aircraft, but is a constant fly-left or fly-right indication of the direction relative to the approach course the aircraft should proceed in order to enter the proportional guidance sector. Control Motion Noise (CMN) means those fluctuations in the guidance which affect aircraft attitude, control surface motion, column motion, and wheel motion. Control motion noise is evaluated by filtering the flight error record with a band-pass filter which has corner frequencies at 0.3 radian/sec and 10 radians/sec for azimuth data and 0.5 radian/sec and 10 radians/sec for elevation data. Data rate means the average number of times per second that transmissions occur for a given function. Differential Phase Shift Keying (DPSK) means differential phase modulation of the radio frequency carrier with relative phase states of 0 degree or 180 degrees. Failure means the inability of an item to perform within previously specified limits. Guard time means an unused period of time provided in the transmitted signal format to allow for equipment tolerances. Integrity means that quality which relates to the trust which can be placed in the correctness of the information supplied by the facility. Mean corrective time means the average time required to correct an equipment failure over a given period, after a service technician reaches the facility. Mean course error means the mean value of the azimuth error along a specified radial of the azimuth function. Mean glide path error means the mean value of the elevation error along a specified glidepath of the elevation function. Mean-time-between-failures (MTBF) means the average time between equipment failures over a given period. Microwave Landing System (MLS) means the MLS selected by ICAO for international standardization. Minimum glidepath means the lowest angle of descent along the zero degree azimuth that is consistent with published approach procedures and obstacle clearance criteria. MLS Approach Reference Datum is a point at a specified height located vertically above the intersection of the runway centerline and the threshold. MLS back azimuth reference datum means a point 15 meters (50 feet) above the runway centerline at the runway midpoint. MLS datum point means a point defined by the intersection of the runway centerline with a vertical plane perpendicular to the centerline and passing through the elevation antenna phase center. Out of coverage indication (OCI) means a signal radiated into areas outside the intended coverage sector, where required, to specifically prevent invalid removal of an airborne warning indication in the presence of misleading guidance information. Path Following Error (PFE) means the guidance perturbations which could cause aircraft displacement from the desired course or glidepath. It is composed of the path following noise and of the mean course error in the case of azimuth functions, or the mean glidepath error in the case of elevation functions. Path following errors are evaluated by filtering the flight error record with a second order low pass filter which has a corner frequency at 0.5 radian/sec for azimuth data or 1.5 radians/sec for elevation data. Path following noise (PFN) means that portion of the guidance signal error which could cause displacement from the actual mean course line or mean glidepath as appropriate. Split-site ground station means the type of ground station in which the azimuth portion of the ground station is located near the stop end of the runway, and the elevation portion is located near the approach end. Time division multiplex (TDM) means that each function is transmitted on the same frequency in time sequence, with a distinct preamble preceding each function transmission." 14:14:3.0.1.4.33.10.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.305 Requests for IFR procedure.,FAA,,,,"(a) Each person who requests an IFR procedure based on an MLS facility which that person owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of §§ 171.309, 171.311, 171.313, 171.315, 171.317, 171.319, and 171.321 and is fabricated and installed in accordance with § 171.323. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and a maintenance manual that meets the requirements of § 171.325. (4) A statement of intent to meet the requirements of this subpart. (5) A showing that the facility has an acceptable level of operational reliability and an acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this subparagraph. (b) FAA inspects and evaluates the MLS facility; it advises the owner of the results, and of any required changes in the MLS facility or in the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the MLS facility for an in-service evaluation by the FAA." 14:14:3.0.1.4.33.10.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.307 Minimum requirements for approval.,FAA,,,,"(a) The following are the minimum requirements that must be met before the FAA approves an IFR procedure for a non-Federal MLS facility: (1) The performance of the MLS facility, as determined by flight and ground inspection conducted by the FAA, must meet the requirements of §§ 171.309, 171.311, 171.313, 171.315, 171.317, 171.319, and 171.321. (2) The fabrication and installation of the equipment must meet the requirements of § 171.323. (3) The owner must agree to operate and maintain the MLS facility in accordance with § 171.325. (4) The owner must agree to furnish operational records as set forth in § 171.327 and agree to allow the FAA to inspect the facility and its operation whenever necessary. (5) The owner must assure the FAA that he will not withdraw the MLS facility from service without the permission of the FAA. (6) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspection made before the MLS facility is commissioned. (b) [Reserved]" 14:14:3.0.1.4.33.10.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.309 General requirements.,FAA,,,,"The MLS is a precision approach and landing guidance system which provides position information and various ground-to-air data. The position information is provided in a wide coverage sector and is determined by an azimuth angle measurement, an elevation angle measurement and a range (distance) measurement. (a) An MLS constructed to meet the requirements of this subpart must include: (1) Approach azimuth equipment, associated monitor, remote control and indicator equipment. (2) Approach elevation equipment, associated monitor, remote control and indicator equipment. (3) A means for the encoding and transmission of essential data words, associated monitor, remote control and indicator equipment. Essential data are basic data words 1, 2, 3, 4, and 6 and auxiliary data words A1, A2 and A3. (4) Distance measuring equipment (DME), associated monitor, remote control and indicator equipment. (5) Remote controls for paragraphs (a) (1), (2), (3), and (4) of this section must include as a minimum on/off and reset capabilities and may be integrated in the same equipment. (6) At locations where a VHF marker beacon (75 MHz) is already installed, it may be used in lieu of the DME equipment. (b) In addition to the equipment required in paragraph (a) of this section the MLS may include: (1) Back azimuth equipment, associated monitor, remote control and indicator equipment. When Back Azimuth is provided, a means for transmission of Basic Data Word 5 and Auxiliary Data Word A4 shall also be provided. (2) A wider proportional guidance sector which exceeds the minimum specified in §§ 171.313 and 171.317. (3) Precision DME, associated monitor, remote control and indicator equipment. (4) VHF marker beacon (75 MHz), associated monitor, remote control and indicator equipment. (5) The MLS signal format will accommodate additional functions (e.g., flare elevation) which may be included as desired. Remote controls for paragraphs (b) (1), (3) and (4) of this section must include as a minimum on/off and reset capabilities, and may be integrated in the same equipment. (6) Provisions for the encoding and transmission of additional auxiliary data words, associated monitor, remote control and indicator equipment. (c) MLS ground equipment must be designed to operate on a nominal 120/240 volt, 60 Hz, 3-wire single phase AC power source and must meet the following service conditions: (1) AC line parameters, DC voltage, elevation and duty: 120 VAC nominal value—102 V to 138 V (±1 V)* 240 VAC nominal value—204 V to 276 V (±2 V)* 60 Hz AC line frequency—57 Hz to 63 Hz (±0.2 Hz)* * Note: Where discrete values of the above frequency or voltages are specified for testing purposes, the tolerances given in parentheses indicated by an asterisk apply to the test instruments used to measure these parameters. Elevation—0 to 3000 meters (10,000 feet) above sea level Duty—Continuous, unattended 120 VAC nominal value—102 V to 138 V (±1 V)* 240 VAC nominal value—204 V to 276 V (±2 V)* 60 Hz AC line frequency—57 Hz to 63 Hz (±0.2 Hz)* * Note: Where discrete values of the above frequency or voltages are specified for testing purposes, the tolerances given in parentheses indicated by an asterisk apply to the test instruments used to measure these parameters. Elevation—0 to 3000 meters (10,000 feet) above sea level Duty—Continuous, unattended (2) Ambient conditions within the shelter for electronic equipment installed in shelters are: Temperature, −10 °C to + 50 °C Relative humidity, 5% to 90% Temperature, −10 °C to + 50 °C Relative humidity, 5% to 90% (3) Ambient conditions for electronic equipment and all other equipment installed outdoors (for example, antenna, field detectors, and shelters): Temperature, −50 °C to + 70 °C Relative humidity, 5% to 100% Temperature, −50 °C to + 70 °C Relative humidity, 5% to 100% (4) All equipment installed outdoors must operate satisfactorily under the following conditions: Wind Velocity: The ground equipment shall remain within monitor limits with wind velocities of up to 70 knots from such directions that the velocity component perpendicular to runway centerline does not exceed 35 knots. The ground equipment shall withstand winds up to 100 knots from any direction without damage. Hail Stones: 1.25 centimeters ( 1/2 inch) diameter. Rain: Provide required coverage with rain falling at a rate of 50 millimeters (2 inches) per hour, through a distance of 9 kilometers (5 nautical miles) and with rain falling at the rate of 25 millimeters (1 inch) per hour for the additional 28 kilometers (15 nautical miles). Ice Loading: Encased in 1.25 centimeters ( 1/2 inch) radial thickness of clear ice. Antenna Radome De-Icing: Down to −6 °C (20 °F) and wind up to 35 knots. Wind Velocity: The ground equipment shall remain within monitor limits with wind velocities of up to 70 knots from such directions that the velocity component perpendicular to runway centerline does not exceed 35 knots. The ground equipment shall withstand winds up to 100 knots from any direction without damage. Hail Stones: 1.25 centimeters ( 1/2 inch) diameter. Rain: Provide required coverage with rain falling at a rate of 50 millimeters (2 inches) per hour, through a distance of 9 kilometers (5 nautical miles) and with rain falling at the rate of 25 millimeters (1 inch) per hour for the additional 28 kilometers (15 nautical miles). Ice Loading: Encased in 1.25 centimeters ( 1/2 inch) radial thickness of clear ice. Antenna Radome De-Icing: Down to −6 °C (20 °F) and wind up to 35 knots. (d) The transmitter frequencies of an MLS must be in accordance with the frequency plan approved by the FAA. (e) The DME component listed in paragraph (a)(4) of this section must comply with the minimum standard performance requirements specified in subpart G of this part. (f) The marker beacon components listed in paragraph (b)(4) of this section must comply with the minimum standard performance requirements specified in subpart H of this part." 14:14:3.0.1.4.33.10.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.311 Signal format requirements.,FAA,,,,"The signals radiated by the MLS must conform to the signal format in which angle guidance functions and data functions are transmitted sequentially on the same C-band frequency. Each function is identified by a unique digital code which initializes the airborne receiver for proper processing. The signal format must meet the following minimum requirements: (a) Frequency assignment. The ground components (except DME/Marker Beacon) must operate on a single frequency assignment or channel, using time division multiplexing. These components must be capable of operating on any one of the 200 channels spaced 300 KHz apart with center frequencies from 5031.0 MHz to 5090.7 MHz and with channel numbering as shown in Table 1a. The operating radio frequencies of all ground components must not vary by more than ±10 KHz from the assigned frequency. Any one transmitter frequency must not vary more than ±50 Hz in any one second period. The MLS angle/data and DME equipment must operate on one of the paired channels as shown in Table 1b. Table 1a —Frequency Channel Plan Table 1b —Channels Notes: * These channels are reserved exclusively for national allotments. ** These channels may be used for national allotment on a secondary basis. The primary reason for reserving these channels is to provide protection for the secondary Surveillance Radar (SSR) system. ▽ 108.0 MHz is not scheduled for assignment to ILS service. The associated DME operating channel No. 17X may be assigned to the emergency service. (b) Polarization. (1) The radio frequency emissions from all ground equipment must be nominally vertically polarized. Any horizontally polarized radio frequency emission component from the ground equipment must not have incorrectly coded angle information such that the limits specified in paragraphs (b) (2) and (3) of this section are exceeded. (2) Rotation of the receiving antenna thirty degrees from the vertically polarized position must not cause the path following error to exceed the allowed error at that location. (c) Modulation requirements. Each function transmitter must be capable of DPSK and continuous wave (CW) modulations of the RF carrier which have the following characteristics. (1) DPSK. The DPSK signal must have the following characteristics: The phase shall advance (or retard) monotonically throughout the transition region. Amplitude modulation during the phase transition period shall not be used. (2) CW. The CW pulse transmissions and the CW angle transmissions as may be required in the signal format of any function must have characteristics such that the requirements of paragraph (d) of this section are met. (d) Radio frequency signal spectrum. The transmitted signal must be such that during the transmission time, the mean power density above a height of 600 meters (2000 feet) does not exceed −100.5 dBW/m 2 for angle guidance and −95.5 dBW/m 2 for data, as measured in a 150 KHz bandwidth centered at a frequency of 840 KHz or more from the assigned frequency. (e) Synchronization. Synchronization between the azimuth and elevation components is required and, in split-site configurations, would normally be accomplished by landline interconnections. Synchronization monitoring must be provided to preclude function overlap. (f) Transmission rates. Angle guidance and data signals must be transmitted at the following average repetition rates: 1 The higher rate is recommended for azimuth scanning antennas with beamwidths greater than two degrees. It should be noted that the time available in the signal format for additional functions is limited when the higher rate is used. 2 Refer to Table 8a. 3 Refer to Table 8c. (g) Transmission sequences. Sequences of angle transmissions which will generate the required repetition rates are shown in Figures 2 and 3. (h) TDM cycle. The time periods between angle transmission sequences must be varied so that exact repetitions do not occur within periods of less than 0.5 second in order to protect against synchronous interference. One such combination of sequences is shown in Figure 4 which forms a full multiplex cycle. Data may be transmitted during suitable open times within or between the sequences. (i) Function Formats (General). Each angle function must contain the following elements: a preamble; sector signals; and a TO and FRO angle scan organized as shown in Figure 5a. Each data function must contain a preamble and a data transmission period organized as shown in Figure 5b. (1) Preamble format. The transmitted angle and date functions must use the preamble format shown in Figure 6. This format consists of a carrier acquisition period of unmodulated CW transmission followed by a receiver synchronization code and a function identification code. The preamble timing must be in accordance with Table 2. (i) Digital codes. The coding used in the preamble for receiver synchronization is a Barker code logic 11101. The time of the last phase transition midpoint in the code shall be the receiver reference time (see Table 2). The function identification codes must be as shown in Table 3. The last two bits (I 11 and I 12 ) of the code are parity bits obeying the equations: I 6 + I 7 + I 8 + I 9 + I 10 + I 11 = Even I 6 + I 8 + I 10 + I 12 = Even (ii) Data modulation. The digital code portions of the preamble must be DPSK modulated in accordance with § 171.311(c)(1) and must be transmitted throughout the function coverage volume. (2) Angle function formats. The timing of the angle transmissions must be in accordance with Tables 4a, 4b, and 5. The actual timing of the TO and FRO scans must be as required to meet the accuracy requirements of §§ 171.313 and 171.317. (i) Preamble. Must be in accordance with requirements of § 171.311(i)(1). Table 2—Preamble Timing 1 1 Applies to all functions transmitted. 2 Reference time for receiver synchronization for all function timing. Table 3—Function Identification Codes (ii) Sector signals. In all azimuth formats, sector signals must be transmitted to provide Morse Code identification, airborne antenna selection, and system test signals. These signals are not required in the elevation formats. In addition, if the signal from an installed ground component results in a valid indication in an area where no valid guidance should exist, OCI signals must be radiated as provided for in the signal format (see Tables 4a, 4b, and 5). The sector signals are defined as follows: (A) Morse Code. DPSK transmissions that will permit Morse Code facility identification in the aircraft by a four letter code starting with the letter “M” must be included in all azimuth functions. They must be transmitted and repeated at approximately equal intervals, not less than six times per minute, during which time the ground subsystem is available for operational use. When the transmissions of the ground subsystem are not available, the identification signal must be suppressed. The audible tone in the aircraft is started by setting the Morse Code bit to logic “1” and stopped by a logic “0” (see Tables 4a and 4b). The identification code characteristics must conform to the following: the dot must be between 0.13 and 0.16 second in duration, and the dash between 0.39 and 0.48 second. The duration between dots and/or dashes must be one dot plus or minus 10%. The duration between characters (letters) must not be less than three dots. When back azimuth is provided, the code shall be transmitted by the approach azimuth and back azimuth within plus or minus 0.08 seconds. (B) Airborne antenna selection. A signal for airborne antenna selection shall be transmitted as a “zero” DPSK signal lasting for a six-bit period (see Tables 4a and 4b). Table 4a —Approach Azimuth Function timing AA 1 The actual commencement and completion of the TO and the FRO scan transmissions are dependent on the amount of proportional guidance provided. The time slots provided shall accommodate a maximum scan of plus or minus 62.0 degrees. Scan timing shall be compatible with accuracy requirements. Table 4b —High Rate Approach Azimuth and Back Azimuth Function Timing 1 The actual commencement and completion of the TO and the FRO scan transmissions are dependent on the amount of proportional guidance provided. The time slots provided will accommodate a maximum scan of plus or minus 42.0 degrees. Scan timing shall be compatible with accuracy requirements. (C) OCI. Where OCI pulses are used, they must be: (1) greater than any guidance signal in the OCI sector; (2) at least 5 dB less than the level of the scanning beam within the proportional guidance sector; and (3) for azimuth functions with clearance signals, at least 5 dB less than the level of the left (right) clearance pulses within the left (right) clearance sector. Table 5—Approach Elevation Function Timing 1 The actual commencement and completion of the TO and FRO scan transmissions are dependent upon the amount of proportional guidance provided. The time slots provided will accommodate a maximum scan of −1.5 degrees to + 29.5 degrees. Scan timing shall be compatible with accuracy requirements. The duration of each pulse measured at the half amplitude point shall be at least 100 microseconds, and the rise and fall times shall be less then 10 microseconds. It shall be permissible to sequentially transmit two pulses in each out-of-coverage indication time slot. Where pulse pairs are used, the duration of each pulse shall be at least 50 microseconds, and the rise and fall times shall be less then 10 microseconds. The transmission of out-of-coverage indication pulses radiated from antennas with overlapping coverage patterns shall be separated by at least 10 microseconds. If desired, two pulses may be sequentially transmitted in each OCI time slot. Where pulse pairs are used, the duration of each pulse must be 45 (±5) microseconds and the rise and fall times must be less than 10 microseconds. (D) System test. Time slots are provided in Tables 4a and 4b to allow radiation of TO and FRO test pulses. However, radiation of these pulses is not required since the characteristics of these pulses have not yet been standardized. (iii) Angle encoding. The encoding must be as follows: (A) General. Azimuth and elevation angles are encoded by scanning a narrow beam between the limits of the proportional coverage sector first in one direction (the TO scan) and then in the opposite direction (the FRO scan). Angular information must be encoded by the amount of time separation between the beam centers of the TO and FRO scanning beam pulses. The TO and FRO transmissions must be symmetrically disposed about the midscan point listed in Tables 4a, 4b, 5, and 7. The midscan point and the center of the time interval between the TO and FRO scan transmissions must coincide with a tolerance of ±10 microseconds. Angular coding must be linear with angle and properly decoded using the formula: where: θ = Receiver angle in degrees. V = Scan velocity in degrees per microsecond. T 0 = Time separation in microseconds between TO and FRO beam centers corresponding to zero degrees. t = Time separation in microseconds between TO and FRO beam centers. where: θ = Receiver angle in degrees. V = Scan velocity in degrees per microsecond. T 0 = Time separation in microseconds between TO and FRO beam centers corresponding to zero degrees. t = Time separation in microseconds between TO and FRO beam centers. The timing requirements are listed in Table 6 and illustrated in Figure 7. (B) Azimuth angle encoding. Each guidance angle transmitted must consist of a clockwise TO scan followed by a counterclockwise FRO scan as viewed from above the antenna. For approach azimuth functions, increasing angle values must be in the direction of the TO scan; for the back azimuth function, increasing angle values must be in the direction of the FRO scan. The antenna has a narrow beam in the plane of the scan direction and a broad beam in the orthogonal plane which fills the vertical coverage. (C) Elevation angle encoding. The radiation from elevation equipment must produce a beam which scans from the horizon up to the highest elevation angle and then scans back down to the horizon. The antenna has a narrow beam in the plane of the scan direction and a broad beam in the orthogonal plane which fills the horizontal coverage. Elevation angles are defined from the horizontal plane containing the antenna phase center; positive angles are above the horizontal and zero angle is along the horizontal. (iv) Clearance guidance. The timing of the clearance pulses must be in accordance with Figure 8. For azimuth elements with proportional coverage of less than ±40 degrees (±20 degrees for back azimuth), clearance guidance information must be provided by transmitting pulses in a TO and FRO format adjacent to the stop/start times of the scanning beam signal. The fly-right clearance pulses must represent positive angles and the fly-left clearance pulses must represent negative angles. The duration of each clearance pulse must be 50 microseconds with a tolerance of ±5 microseconds. The transmitter switching time between the clearance pulses and the scanning beam transmissions must not exceed 10 microseconds. The rise time at the edge of each clearance pulse must be less than 10 microseconds. Within the fly-right clearance guidance section, the fly-right clearance guidance signal shall exceed scanning beam antenna sidelobes and other guidance and OCI signals by at least 5 dB; within the fly-left clearance guidance sector, the fly left clearance guidance signal shall exceed scanning beam antenna sidelobes and all other guidance and OCI signals by at least 5 dB; within the proportional guidance sector, the clearance guidance signals shall be at least 5dB below the proportional guidance signal. Optionally, clearance guidance may be provided by scanning throughout the approach guidance sector. For angles outside the approach azimuth proportional coverage limits as set in Basic Data Word One (Basic Data Word 5 for back azimuth), proper decode and display of clearance guidance must occur to the limits of the guidance region. Where used, clearance pulses shall be transmitted adjacent to the scanning beam signals at the edges of proportional coverage as shown in Figure 8. The proportional coverage boundary shall be established at one beamwidth inside the scan start/stop angles, such that the transition between scanning beam and clearance signals occurs outside the proportional coverage sector. When clearance pulses are provided in conjunction with a narrow beamwidth (e.g., one degree) scanning antenna, the scanning beam antenna shall radiate for 15 microseconds while stationary at the scan start/stop angles. (3) Data function format. Basic data words provide equipment characteristics and certain siting information. Basic data words must be transmitted from an antenna located at the approach azimuth or back azimuth site which provides coverage throughout the appropriate sector. Data function timing must be in accordance with Table 7a. Table 6—Angle Scan Timing Constants Table 7a —Basic Data Function Timing 1 The previous event time slot ends at this time. Table 7b —Auxiliary Data Function Timing—(Digital) Table 7c —Auxiliary Data Function Timing—(Alphanumeric) (i) Preamble. Must be in accordance with requirements of § 171.311(i)(1). (ii) Data transmissions. Basic data must be transmitted using DPSK modulation. The content and repetition rate of each basic data word must be in accordance with Table 8a. For data containing digital information, binary number 1 must represent the lower range limit with increments in binary steps to the upper range limit shown in Table 8a. Data containing digital information shall be transmitted with the least significant bit first. (j) Basic Data word requirements. Basic Data shall consist of the items specified in Table 8a. Basic Data word contents shall be defined as follows: (1) Approach azimuth to threshold distance shall represent the minimum distance between the Approach Azimuth antenna phase center and the vertical plane perpendicular to the centerline which contains the landing threshold. (2) Approach azimuth proportional coverage limit shall represent the limit of the sector in which proportional approach azimuth guidance is transmitted. (3) Clearance signal type shall represent the type of clearance when used. Pulse clearance is that which is in accordance with § 171.311 (i) (2) (iv). Scanning Beam (SB) clearance indicates that the proportional guidance sector is limited by the proportional coverage limits set in basic data. Table 8a —Basic Data Words Note 1: Transmit at intervals of 1.0 second or less throughout the Approach Azimuth guidance sector, except when Back Azimuth guidance is provided. See note 8. Note 3: Characters are encoded using the International Alphabet Number 5, (IA-5): Note 4: Coding for status bit: 0 = Function not radiated, or radiated in test mode (not reliable for navigation). 1 = Function radiated in normal mode (for Back Azimuth, this also indicates that a Back Azimuth transmission follows). Note 5: Date items which are not applicable to a particular ground equipment shall be transmitted as all zeros. Note 6: Coding for status bits: Note 7: The value coded shall be the actual beamwidth (as defined in § 171.311 (j)(9) rounded to the nearest 0.5 degree. Note 8: When back Azimuth guidance is provided, Data Words 4 and 6 shall be transmitted at intervals of 1.33 seconds or less throughout the Approach Azimuth coverage and 4 seconds or less throughout the Back Azimuth coverage. Note 9: When Back Azimuth guidance is provided, Data Word 5 shall be transmitted at an interval of 1.33 seconds or less throughout the Back Azimuth coverage sector and 4 seconds or less throughout the Approach Azimuth coverage sector. Note 10: Coding for status bit: 0 = Function not radiated, or radiated in test mode (not reliable for navigation). 1 = Function radiated in normal mode. (4) Minimum glidepath the lowest angle of descent along the zero degree azimuth that is consistent with published approach procedures and obstacle clearance criteria. (5) Back azimuth status shall represent the operational status of the Back Azimuth equipment. (6) DME status shall represent the operational status of the DME equipment. (7) Approach azimuth status shall represent the operational status of the approach azimuth equipment. (8) Approach elevation status shall represent the operational status of the approach elevation equipment. (9) Beamwidth the width of the scanning beam main lobe measured at the −3 dB points and defined in angular units on the antenna boresight, in the horizontal plane for the azimuth function and in the vertical plane for the elevation function. (10) DME distance shall represent the minimum distance between the DME antenna phase center and the vertical plane perpendicular to the runway centerline which contains the MLS datum point. (11) Approach azimuth magnetic orientation shall represent the angle measured in the horizontal plane clockwise from Magnetic North to the zero-degree angle guidance radial originating from the approach azimuth antenna phase center. The vertex of the measured angle shall be at the approach azimuth antenna phase center. For example, this data item would be encoded 090 for an approach azimuth antenna serving runway 27 (assuming the magnetic heading is 270 degrees) when sited such that the zero degree radial is parallel to centerline. (12) Back azimuth magnetic orientation shall represent the angle measured in the horizontal plane clockwise from Magnetic North to the zero-degree angle guidance radial originating from the Back Azimuth antenna. The vertex of the measured angle shall be at the Back Azimuth antenna phase center. For example, this data item would be encoded 270 for a Back Azimuth Antenna serving runway 27 (assuming the magnetic heading is 270 degrees) when sited such that the zero degree radial is parallel to centerline. (13) Back azimuth proportional coverage limit shall represent the limit of the sector in which proportional back azimuth guidance is transmitted. (14) MLS ground equipment identification shall represent the last three characters of the system identification specified in § 171.311(i)(2). The characters shall be encoded in accordance with International Alphabet No. 5 (IA-5) using bits b 1 through b 6 . Bit b 7 of this code may be reconstructed in the airborne receiver by taking the complement of bit b 6 . (k) Residual radiation. The residual radiation of a transmitter associated with an MLS function during time intervals when it should not be transmitting shall not adversely affect the reception of any other function. The residual radiation of an MLS function at times when another function is radiating shall be at least 70 dB below the level provided when transmitting. (l) Symmetrical scanning. The TO and FRO scan transmissions shall be symmetrically disposed about the mid-scan point listed in Tables 4a, 4b and 5. The mid-scan point and the center of the time interval between the TO and FRO scan shall coincide with a tolerance of plus or minus 10 microseconds. (m) Auxiliary data —(1) Addresses. Three function identification codes are reserved to indicate transmission of Auxiliary Data A, Auxiliary Data B, and Auxiliary Data C. Auxiliary Data A contents are specified below, Auxiliary Data B contents are reserved for future use, and Auxiliary Data C contents are reserved for national use. The address codes of the auxiliary data words shall be as shown in Table 8b. (2) Organization and timing. The organization and timing of digital auxiliary data must be as specified in Table 7b. Data containing digital information must be transmitted with the least significant bit first. Alphanumeric data characters must be encoded in accordance with the 7-unit code character set as defined by the American National Standard Code for Information Interchange (ASCII). An even parity bit is added to each character. Alphanumeric data must be transmitted in the order in which they are to be read. The serial transmission of a character must be with the lower order bit transmitted first and the parity bit transmitted last. The timing for alphanumeric auxiliary data must be as shown in Table 7c. (3) Auxiliary Data A content: The data items specified in Table 8c are defined as follows: (i) Approach azimuth antenna offset shall represent the minimum distance between the Approach Azimuth antenna phase center and the vertical plane containing the runway centerline. (ii) Approach azimuth to MLS datum point distance shall represent the minimum distance between the Approach Azimuth antenna phase center and the vertical plane perpendicular to the centerline which contains the MLS datum point. (iii) Approach azimuth alignment with runway centerline shall represent the minimum angle between the approach azimuth antenna zero-degree guidance plane and the runway certerline. (iv) Approach azimuth antenna coordinate system shall represent the coordinate system (planar or conical) of the angle data transmitted by the approach azimuth antenna. (v) Approach elevation antenna offset shall represent the minimum distance between the elevation antenna phase center and the vertical plane containing the runway centerline. (vi) MLS datum point to threshold distance shall represent the distance measured along the runway centerline from the MLS datum point to the runway threshold. (vii) Approach elevation antenna height shall represent the height of the elevation antenna phase center relative to the height of the MLS datum point. (viii) DME offset shall represent the minimum distance between the DME antenna phase center and the vertical plane containing the runway centerline. (ix) DME to MLS datum point distance shall represent the minimum distance between the DME antenna phase center and the vertical plane perpendicular to the centerline which contains the MLS datum point. (x) Back azimuth antenna offset shall represent the minimum distance between the back azimuth antenna phase center and the vertical plane containing the runway centerline. (xi) Back azimuth to MLS datum point distance shall represent the minimum distance between the Back Azimuth antenna and the vertical plane perpendicular to the centerline which contains the MLS datum point. (xii) Back azimuth antenna alignment with runway centerline shall represent the minimum angle between the back azimuth antenna zero-degree guidance plane and the runway centerline." 14:14:3.0.1.4.33.10.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.313 Azimuth performance requirements.,FAA,,,,"This section prescribes the performance requirements for the azimuth equipment of the MLS as follows: (a) Approach azimuth coverage requirements. The approach azimuth equipment must provide guidance information in at least the following volume of space (see Figure 9): Table 8b —Auxiliary Data Word Address Codes Note 1: Parity bits I 19 and I 20 are chosen to satisfy the equations: I 13 + I 14 + I 15 + I 16 + I 17 + I 18 + I 19 = EVEN I 14 + I 16 + I 18 + I 20 = EVEN Note 1: Parity bits I 19 and I 20 are chosen to satisfy the equations: I 13 + I 14 + I 15 + I 16 + I 17 + I 18 + I 19 = EVEN I 14 + I 16 + I 18 + I 20 = EVEN Table 8c—Auxiliary Data Parity bits I 70 to I 76 are chosen to satisfy the equations which follow: For BIT I 70 : Even = (I 13 + ... + I 18 ) + I 20 + I 22 + I 24 + I 25 + I 28 + I 29 + I 31 + I 32 + I 33 + I 35 + I 36 + I 38 + I 41 + I 44 + I 45 + I 46 + I 50 + (I 52 + ... + I 55 ) + I 58 + I 60 + I 64 + I 65 + I 70 For BIT I 71 : Even = (I 14 + ... + I 19 ) + I 21 + I 23 + I 25 + I 26 + I 29 + I 30 + I 32 + I 33 + I 34 + I 36 + I 37 + I 39 + I 42 + I 45 + I 46 + I 47 + I 51 + (I 53 + ... + I 56 ) + I 59 + I 61 + I 65 + I 66 + I 71 For BIT I 72 : Even = (I 15 + ... + I 20 ) + I 22 + I 24 + I 26 + I 27 + I 30 + I 31 + I 33 + I 34 + I 35 + I 37 + I 38 + I 40 + I 43 + I 46 + I 47 + I 48 + I 52 + (I 54 + ... + I 57 ) + I 60 + I 62 + I 66 + I 67 + I 72 For BIT I 73 : Even = (I 16 + ... + I 21 ) + I 23 + I 25 + I 27 + I 28 + I 31 + I 32 + I 34 + I 35 + I 36 + I 38 + I 39 + I 41 + I 44 + I 47 + I 48 + I 49 + I 53 + (I 55 + ... + I 58 ) + I 61 + I 63 + I 67 + I 68 + I 73 For BIT I 74 : Even = (I 17 + ... + I 22 ) + I 24 + I 26 + I 28 + I 29 + I 32 + I 33 + I 35 + I 36 + I 37 + I 39 + I 40 + I 42 + I 45 + I 48 + I 49 + I 50 + I 54 + (I 56 + ... + I 59 ) + I 62 + I 64 + I 68 + I 69 + I 74 For BIT I 75 : Even = (I 13 + ... + I 17 ) + I 19 + I 21 + I 23 + I 24 + I 27 + I 28 + I 30 + I 31 + I 32 + I 34 + I 35 + I 37 + I 40 + I 43 + I 44 + I 45 + I 49 + (I 51 + ... + I 54 ) + I 57 + I 59 + I 63 + I 64 + I 69 + I 75 For BIT I 76 : Even = I 13 + I 14 + ... + I 75 + I 76 Code for I 56 is: 0 = conical; 1 = planar. The convention for the coding of negative numbers is as follows: − MSB is the sign bit; 0 = + ; 1 = −. —Other bits represent the absolute value. The convention for the antenna location is as follows: As viewed from the MLS approach reference datum looking toward the datum point, a positive number shall represent a location to the right of the runway centerline (lateral offset) or above the runway (vertical offset), or towards the stop end of the runway (longitudinal distance). The convention for the antenna alignment is as follows: As viewed from above, a positive number shall represent clockwise rotation from the runway centerline to the respective zero-degree guidance plane. Data Word A3 is transmitted at intervals of 1.0 seconds or less throughout the approach Azimuth coverage sector, except when back Azimuth guidance is provided. Where back Azimuth is provided transmit at intervals of 1.33 seconds or less throughout the approach Azimuth sector and 4.0 seconds or less throughout the back Azimuth coverage sector. When back Azimuth guidance is provided, transmit at intervals of 1.33 seconds or less throughout the back Azimuth coverage sector and 4.0 seconds or less throughout the approach Azimuth coverage sector. The designation “A1” represents the function identification code for “Auxiliary Data A” and address code number 1. (1) Horizontally within a sector plus or minus 40 degrees about the runway centerline originating at the datum point and extending in the direction of the approach to 20 nautical miles from the runway threshold. The minimum proportional guidance sector must be plus or minus 10 degrees about the runway centerline. Clearance signals must be used to provide the balance of the required coverage, where the proportional sector is less than plus or minus 40 degrees. When intervening obstacles prevent full coverage, the ±40° guidance sector can be reduced as required. For systems providing ±60° lateral guidance the coverage requirement is reduced to 14 nm beyond ±40°. (2) Vertically between: (i) A conical surface originating 2.5 meters (8 feet) above the runway centerline at threshold inclined at 0.9 degree above the horizontal. (ii) A conical surface originating at the azimuth ground equipment antenna inclined at 15 degrees above the horizontal to a height of 6,000 meters (20,000 feet). (iii) Where intervening obstacles penetrate the lower surface, coverage need be provided only to the minimum line of sight. (3) Runway region: (i) Proportional guidance horizontally within a sector 45 meters (150 feet) each side of the runway centerline beginning at the stop end and extending parallel with the runway centerline in the direction of the approach to join the approach region. This requirement does not apply to offset azimuth installations. (ii) Vertically between a horizontal surface which is 2.5 meters (8 feet) above the farthest point of runway centerline which is in line of sight of the azimuth antenna, and in a conical surface originating at the azimuth ground equipment antenna inclined at 20 degrees above the horizontal up to a height to 600 meters (2,000 feet). This requirement does not apply to offset azimuth installations. (4) Within the approach azimuth coverage sector defined in paragraphs (a) (1), and (2) and (3) of this section, the power densities must not be less than those shown in Table 9 but the equipment design must also allow for: (i) Transmitter power degradation from normal by −1.5 dB; Table 9—Minimum Power Density Within Coverage Boundaries(dBW/m 2 ) (ii) Rain loss of −2.2 dB at the longitudinal coverage extremes. (b) Siting requirements. The approach azimuth antenna system must, except as allowed in paragraph (c) of this section: (1) Be located on the extension of the centerline of the runway beyond the stop end; (2) Be adjusted so that the zero degree azimuth plane will be a vertical plane which contains the centerline of the runway served; (3) Have the minimum height necessary to comply with the coverage requirements prescribed in paragraph (a) of this section; (4) Be located at a distance from the stop end of the runway that is consistent with safe obstruction clearance practices; (5) Not obscure any light of an approach lighting system; and (6) Be installed on frangible mounts or beyond the 300 meter (1,000 feet) light bar. (c) On runways where limited terrain prevents the azimuth antenna from being positioned on the runway centerline extended, and the cost of the land fill or a tall tower antenna support is prohibitive, the azimuth antenna may be offset. (d) Antenna coordinates. The scanning beams transmitted by the approach azimuth equipment within ±40° of the centerline may be either conical or planar. (e) Approach azimuth accuracy. (1) The system and subsystem errors shall not exceed those listed in Table 10 at the approach reference datum. At the approach reference datum, temporal sinusoidal noise components shall not exceed 0.025 degree peak in the frequency band 0.01 Hz to 1.6 Hz, and the CMN shall not exceed 0.10 degree. From the approach reference datum to the coverage limit, the PFE, PFN and CMN limits, expressed in angular terms, shall be allowed to linearly increase as follows: (i) With distance along the runway centerline extended, by a factor of 1.2 for the PFE and PFN limits and to ±0.10 degree for the CMN limits. (ii) With azimuth angle, by a factor of 1.5 at the ±40 degree and a factor of 2.0 at the ±60 degree azimuth angles for the PFE, PFN and CMN limits. (iii) With elevation angle from + 9 degrees to + 15 degrees, by a factor of 1.5 for the PFE and PFN limits. (iv) Maximum angular limits. The PFE limits shall not exceed ±0.25 degree in any coverage region below an elevation angle of + 9 degrees nor exceed ±0.50 degree in any coverage region above that elevation angle. The CMN limits shall not exceed ±0.10 degree in any coverage region within ±10 degrees of runway centerline extended nor exceed ±0.20 degree in any other region within coverage. It is desirable that the CMN not exceed ±0.10 degree throughout the coverage. (f) Approach azimuth antenna characteristics are as follows: (1) Drift. Any azimuth angle as encoded by the scanning beam at any point within the proportional coverage must not vary more than ±0.07 degree over the range of service conditions specified in § 171.309(d) without the use of internal environmental controls. Multipath effects are excluded from this requirement. (2) Beam pointing errors. The azimuth angle as encoded by the scanning beam at any point within ±0.5 degree of the zero degree azimuth must not deviate from the true azimuth angle at that point by more than ±.05 degree. Multipath and drift effects are excluded from this requirement. Table 10—Approach Azimuth Accuracies at the Approach Reference Datum Notes: 1 Includes errors due to ground and airborne equipment and propagation effects. 2 The system PFN component must not exceed ±3.5 meters (11.5 feet). 3 The mean (bias) error component contributed by the ground equipment should not exceed ±10 feet. 4 The system control motion noise must not exceed 0.1 degree. 5 The airborne subsystem angular errors are provided for information only. (3) Antenna alignment. The antenna must be equipped with suitable optical, electrical or mechanical means or any combination of the three, to bring the zero degree azimuth radial into coincidence with the approach reference datum (for centerline siting) with a maximum error of 0.02 degree. Additionally, the azimuth antenna bias adjustment must be electronically steerable at least to the monitor limits in steps not greater than 0.005 degree. (4) Antenna far field patterns in the plane of scan. On boresight, the azimuth antenna mainlobe pattern must conform to Figure 10, and the beamwidth must be such that, in the installed environment, no significant lateral reflections of the mainlobe exist along the approach course. In any case the beamwidth must not exceed three degrees. Anywhere within coverage the −3 dB width of the antenna mainlobe, while scanning normally, must not be less than 25 microseconds (0.5 degree) or greater than 250 microseconds (5 degrees). The antenna mainlobe may be allowed to broaden from the value at boresight by a factor of 1/cosθ, where θ is the angle off boresight. The sidelobe levels must be as follows: (i) Dynamic sidelobe levels. With the antenna scanning normally, the dynamic sidelobe level that is detected by a receiver at any point within the proportional coverage sector must be down at least 10 dB from the peak of the main beam. Outside the coverage sector, the radiation from the scanning beam antenna must be of such a nature that receiver warning will not be removed or suitable OCI signals must be provided. (ii) Effective sidelobe levels. With the antenna scanning normally, the sidelobe levels in the plane of scan must be such that, in the installed environment, the CMN contributed by sidelobe reflections will not exceed the angular equivalent of 9 feet at approach reference datum over the required range of aircraft approach speeds. (5) Antenna far field pattern in the vertical plane. The azimuth antenna free space radiation pattern below the horizon must have a slope of at least −8 dB/degree at the horizon and all sidelobes below the horizon must be at least 13 dB below the pattern peak. The antenna radiation pattern above the horizon must satisfy both the system coverage requirements and the spurious radiation requirement. (6) Data antenna. The data antenna must have horizontal and vertical patterns as required for its function. (g) Back azimuth coverage requirements. The back azimuth equipment where used must provide guidance information in at least the following volume of space (see Figure 11): (1) Horizontally within a sector ±40 degrees about the runway centerline originating at the back azimuth ground equipment antenna and extending in the direction of the missed approach at least to 20 nautical miles from the runway stop end. The minimum proportional guidance sector must be ±10 degrees about the runway centerline. Clearance signals must be used to provide the balance of the required coverage where the proportional sector is less than ±40 degrees. (2) Vertically in the runway region between: (i) A horizontal surface 2.5 meters (8 feet) above the farthest point of runway centerline which is in line of sight of the azimuth antenna, and, (ii) A conical surface originating at the azimuth ground equipment antenna inclined at 20 degrees above the horizontal up to a height of 600 meters (2000 feet). (3) Vertically in the back azimuth region between: (i) A conical surface originating 2.5 meters (8 feet) above the runway stop end, included at 0.9 degree above the horizontal, and, (ii) A conical surface orginating at the missed approach azimuth ground equipment antenna, inclined at 15 degrees above the horizontal up to a height of 1500 meters (5000 feet). (iii) Where obstacles penetrate the lower coverage limits, coverage need be provided only to minimum line of sight. (4) Within the back azimuth coverage sector defined in paragraph (q) (1), (2), and (3) of this section the power densities must not be less than those shown in Table 9, but the equipment design must also allow for: (i) Transmitter power degradation from normal −1.5 dB. (ii) Rain loss of −2.2 dB at the longitudinal coverage extremes. (h) Back azimuth siting. The back azimuth equipment antenna must: (1) Normally be located on the extension of the runway centerline at the threshold end; (2) Be adjusted so that the vertical plane containing the zero degree course line contains the back azimuth reference datum; (3) Have minimum height necessary to comply with the course requirements prescribed in paragraph (g) of this section; (4) Be located at a distance from the threshold end that is consistent with safe obstruction clearance practices; (5) Not obscure any light of an approach lighting system; and (6) Be installed on frangible mounts or beyond the 300 meter (1000 feet) light bar. (i) Back azimuth antenna coordinates. The scanning beams transmitted by the back azimuth equipment may be either conical or planar. (j) Back azimuth accuracy. The requirements specified in § 171.313(e) apply except that the reference point is the back azimuth reference datum. (k) Back azimuth antenna characteristics. The requirements specified in § 171.313(f) apply. (l) Scanning conventions. Figure 12 shows the approach azimuth and back azimuth scanning conventions. (m) False guidance. False courses which can be acquired and tracked by an aircraft shall not exist anywhere either inside or outside of the MLS coverage sector. False courses which exist outside of the minimum coverage sector may be suppressed by the use of OCI. False courses may be due to (but not limited to) MLS airborne receiver acquisition of the following types of false guidance: reflections of the scanning beam, scanning beam antenna sidelobes and grating lobes, and incorrect clearance." 14:14:3.0.1.4.33.10.3.8,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.315 Azimuth monitor system requirements.,FAA,,,,"(a) The approach azimuth or back azimuth monitor system must cause the radiation to cease and a warning must be provided at the designated control point if any of the following conditions persist for longer than the periods specified: (1) There is a change in the ground equipment contribution to the mean course error component such that the path following error at the reference datum or in the direction of any azimuth radial, exceeds the limits specified in §§ 171.313(e)(1) or 171.313(j) for a period of more than one second. The above requirement and the requirement to limit the ground equipment mean error to ±10 ft. can be satisfied by the following procedure. The integral monitor alarm limit should be set to the angular equivalent of ±10 ft. at the approach reference datum. This will limit the electrical component of the mean course error to ±10 ft. The field monitor alarm limit should be set such that with the mean course error at the alarm limit the total allowed PFE is not exceeded on any commissioned approach course from the limit of coverage to an altitude of 100 feet. (2) There are errors in two consecutive transmissions of Basic Data Words 1, 2, 4 or 5. (3) There is a reduction in the radiated power to a level not less than that specified in §§ 171.313(a)(4) or 171.313(g)(4) for a period of more than one second. (4) There is an error in the preamble DPSK transmissions which occurs more than once in any one second period. (5) There is an error in the time division multiplex synchronization of a particular azimuth function that the requirement specified in § 171.311(e) is not satisfied and if this condition persists for more than one second. (6) A failure of the monitor is detected. (b) Radiation of the following fuctions must cease and a warning provided at the designated control point if there are errors in 2 consecutive transmissions: (1) Morse Code Identification, (2) Basic Data Words 3 and 6, (3) Auxiliary Data Words. (c) The period during which erroneous guidance information is radiated must not exceed the periods specified in § 171.315(a). If the fault is not cleared within the time allowed, the ground equipment must be shut down. After shutdown, no attempt must be made to restore service until a period of 20 seconds has elapsed." 14:14:3.0.1.4.33.10.3.9,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,J,Subpart J—Microwave Landing System (MLS),,§ 171.317 Approach elevation performance requirements.,FAA,,,,"This section prescribes the performance requirements for the elevation equipment components of the MLS as follows: (a) Elevation coverage requirements. The approach elevation facility must provide proportional guidance information in at least the following volume of space (see Figure 13): (1) Laterally within a sector originating at the datum point which is at least equal to the proportional guidance sector provided by the approach azimuth ground equipment. (2) Longitudinally from 75 meters (250 feet) from the datum point to 20 nautical miles from threshold in the direction of the approach. (3) Vertically within the sector bounded by: (i) A surface which is the locus of points 2.5 meters (8 feet) above the runway surface; (ii) A conical surface originating at the datum point and inclined 0.9 degree above the horizontal and, (iii) A conical surface originating at the datum point and inclined at 15.0 degrees above the horizontal up to a height of 6000 meters (20,000 feet). Where the physical characteristics of the approach region prevent theachievement of the standards under paragraphs (a) (1), (2), and (3) of this section, guidance need not be provided below a conical surface originating at the elevation antenna and inclined 0.9 degree above the line of sight. (4) Within the elevation coverage sector defined in paragraphs (a) (1), (2) and (3) of this section, the power densities must not be less than those shown in Table 9, but the equipment design must also allow for: (i) Transmitter power degradation from normal by −1.5 dB. (ii) Rain loss of −2.2 dB at the coverage extremes. (b) Elevation siting requirements. The Elevation Antenna System must: (1) Be located as close to runway centerline as possible (without violating obstacle clearance criteria). (2) Be located near runway threshold such that the asymptote of the minimum glidepath crosses the threshold of the runway at the Approach Reference Datum height. Normally, the minimum glidepath should be 3 degrees and the Approach Reference Datum height should be 50 feet. However, there are circumstances where other glideslopes and reference datum heights are appropriate. Some of these instances are discussed in FAA Order 8260.34 (Glide Slope Threshold Crossing Height Requirements) and Order 8260.3 (IFR Approval of MLS.) (3) Be located such that the MLS Approach Reference Datum and ILS Reference Datum heights are coincident within a tolerance of 3 feet when MLS is installed on a runway already served by an ILS. This requirement applies only if the ILS glide slope is sited such that the height of the reference datum meets the requirements of FAA Order 8260.34. (c) Antenna coordinates. The scanning beams transmitted by the elevation subsystem must be conical. (d) Elevation accuracy. (1) The accuracies shown in Table 13 are required at the approach reference datum. From the approach reference datum to the coverage limit, the PFE, PFN and CMN limits shall be allowed to linearly increase as follows: (i) With distance along the runway centerline extended at the minimum glide path angle, by a factor of 1.2 for the PFE and PFN limits and to ±0.10 degree for the CMN limits; (ii) With azimuth angle, from runway centerline extended to the coverage extreme, by a factor of 1.2 for the PFE and PFN limits and by a factor of 2.0 for the CMN limits; (iii) With increasing elevation angles from + 3 degrees to + 15 degrees, by a factor of 2.0 for the PFE and PFN limits; Table 13—Elevation Accuracies at the Approach Reference Datum Notes: 1 Includes errors due to ground and airborne equipment and propagation effects. 2 The system PFN component must not exceed ±0.087 degree. 3 The mean (bias) error component contributed by the ground equipment should not exceed ±0.067 degree. 4 The airborne subsystem angular errors are provided for information only. (iv) With decreasing elevation angle from + 3 degrees (or 60% of the minimum glide path angle, whichever is less) to the coverage extreme, by a factor of 3 for the PFE, PFN and CMN limits; and (v) Maximum angular limits. the CMN limits shall not exceed ±0.10 degree in any coverage region within ±10 degrees laterally of runway centerline extended which is above the elevation angle specified in (iv) above. It is desirable that the CMN not exceed ±0.10 degree throughout the coverage region above the elevation angle specified in paragraph (d)(1)(iv) of this section. (2) The system and ground subsystem accuracies shown in Table 13 are to be demonstrated at commissioning as maximum error limits. Subsequent to commissioning, the accuracies are to be considered at 95% probability limits. (e) Elevation antenna characteristics are as follows: (1) Drift. Any elevation angle as encoded by the scanning beam at any point within the coverage sector must not vary more than 0.04 degree over the range of service conditions specified in § 171.309(d) without the use of internal environmental controls. Multipath effects are excluded from this requirement. (2) Beam pointing errors. The elevation angle as encoded by the scanning beam at any point within the coverage sector must not deviate from the true elevation angle at that point by more than ±0.04 degree for elevation angles from 2.5° to 3.5°. Above 3.5° these errors may linearly increase to ±0.1 degree at 7.5°. Multipath and drift effects are excluded from this requirement. (3) Antenna alignment. The antenna must be equipped with suitable optical, electrical, or mechanical means or any combination of the three, to align the lowest operationally required glidepath to the true glidepath angle with a maximum error of 0.01 degree. Additionally, the elevation antenna bias adjustment must be electronically steerable at least to the monitor limits in steps not greater than 0.005 degrees. (4) Antenna far field patterns in the plane of scan. On the lowest operationally required glidepath, the antenna mainlobe pattern must conform to Figure 10, and the beamwidth must be such that in the installed environment, no significant ground reflections of the mainlobe exist. In any case, the beamwidth must not exceed 2 degrees. The antenna mainlobe may be allowed to broaden from the value at boresight by a factor of 1/cosθ, where θ is the angle of boresight. Anywhere within coverage, the −3 dB width of the antenna mainlobe, while scanning normally, must not be less than 25 microseconds (0.5 degrees) or greater than 250 microseconds (5 degrees). The sidelobe levels must be as follows: (i) Dynamic sidelobe levels. With the antenna scanning normally, the dynamic sidelobe level that is detected by a receiver at any point within the proportional coverage sector must be down at least 10 dB from the peak of the mainlobe. Outside the proportional coverage sector, the radiation from the scanning beam antenna must be of such a nature that receiver warnings will not be removed or a suitable OCI signal must be provided. (ii) Effective sidelobe levels. With the antenna scanning normally, the sidelobe levels in the plane of scan must be such that, when reflected from the ground, the resultant PFE along any glidepath does not exceed 0.083 degrees. (5) Antenna far field pattern in the horizontal plane. The horizontal pattern of the antenna must gradually de-emphasize the signal away from antenna boresight. Typically, the horizontal pattern should be reduced by at least 3 dB at 20 degrees off boresight and by at least 6 dB at 40 degrees off boresight. Depending on the actual multipath conditions, the horizontal radiation patterns may require more or less de-emphasis. (6) Data antenna. The data antenna must have horizontal and vertical patterns as required for its function. (f) False guidance. False courses which can be acquired and tracked by an aircraft shall not exist anywhere either inside or outside of the MLS coverage sector. False courses which exist outside of the minimum coverage sector may be suppressed by the use of OCI. False courses may be due to (but not limited to) MLS airborne receiver acquisition of the following types of false guidance: reflections of the scanning beam and scanning beam antenna sidelobes and grating lobes." 14:14:3.0.1.4.33.2.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.21 Scope.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-2, 31 FR 5408, Apr. 6, 1966; Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]","(a) This subpart sets forth minimum requirements for the approval and operation of non-Federal, nondirectional radio beacon facilities that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. (b) A nondirectional radio beacon (“H” facilities domestically—NDB facilities internationally) radiates a continuous carrier of approximately equal intensity at all azimuths. The carrier is modulated at 1020 cycles per second for station identification purposes." 14:14:3.0.1.4.33.2.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.23 Requests for IFR procedure.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]","(a) Each person who requests an IFR procedure based on a nondirectional radio beacon facility that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of § 171.27 and is installed in accordance with § 171.29. (2) A proposed procedure for operating the facility. (3) A proposed maintenance arrangement and a maintenance manual that meets the requirements of § 171.31. (4) A statement of intention to meet the requirements of this subpart. (5) A showing that the facility has an acceptable level of operational reliability and an acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this subparagraph. (b) After the FAA inspects and evaluates the facility, it advises the owner of the results and of any required changes in the facility or the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the facility for an in-service evaluation by the FAA." 14:14:3.0.1.4.33.2.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.25 Minimum requirements for approval.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-6, 35 FR 10288, June 24, 1970]","(a) The following are the minimum requirements that must be met before the FAA will approve an IFR procedure for a non-Federal, nondirectional radio beacon facility under this subpart: (1) The facility's performances, as determined by air and ground inspection, must meet the requirements of § 171.27. (2) The installation of the equipment must meet the requirements of § 171.29. (3) The owner must agree to operate and maintain the facility in accord- ance with § 171.31. (4) The owner must agree to furnish periodic reports, as set forth in § 171.33, and agree to allow the FAA to inspect the facility and its operation whenever necessary. (5) The owner must assure the FAA that he will not withdraw the facility from service without the permission of the FAA. (6) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspections made before the facility is commissioned, except that the Federal Aviation Administration may bear certain of these costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the FAA commissions the facility as a prerequisite to its approval for use in an IFR procedure. The approval is withdrawn at any time the facility does not continue to meet those requirements. In addition, the facility may be de-commissioned whenever the frequency channel is needed for higher priority common system service." 14:14:3.0.1.4.33.2.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.27 Performance requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]","(a) The facility must meet the performance requirements set forth in the “International Standards and Recommended Practices, Aeronautical Telecommunications, Part I, paragraph 3.4” (Annex 10 to the Convention on International Civil Aviation), except that identification by on-off keying of a second carrier frequency, separated from the main carrier by 1020 Hz plus or minus 50 Hz, is also acceptable. (b) The facility must perform in accordance with recognized and accepted good electronic engineering practices for the desired service. (c) Ground inspection consists of an examination of the design features of the equipment to determine (based on recognized and accepted good engineering practices) that there will not be conditions that will allow unsafe operations because of component failure or deterioration. (d) Flight tests to determine the facility's adequacy for operational requirements and compliance with applicable “Standards and Recommended Practices” are conducted in accord- ance with the “U.S. Standard Flight Inspection Manual”, particularly section 207. The original test is made by the FAA and later tests shall be made under arrangements, satisfactory to the FAA, that are made by the owner." 14:14:3.0.1.4.33.2.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.29 Installation requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-16, 56 FR 65664, Dec. 17, 1991]","(a) The facility must be installed according to accepted good engineering practices, applicable electric and safety codes, and FCC licensing requirements. (b) The facility must have a reliable source of suitable primary power. (c) Dual transmitting equipment may be required to support some IFR procedures. (d) A facility intended for use as an instrument approach aid for an airport must have or be supplemented by (depending on the circumstances) the following ground-air or landline communications services: (1) At facilities outside of and not immediately adjacent to controlled airspace, there must be ground-air communications from the airport served by the facility. Voice on the aid controlled from the airport is acceptable. (2) At facilities within or immediately adjacent to controlled airspace, there must be the ground-air communications required by paragraph (d)(1) of this section and reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communication facility. Paragraphs (d) (1) and (2) of this section are not mandatory at airports where an adjacent FAA facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of paragraphs (d) (1) and (2) of this section may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communications facility, if an adjacent FAA facility can communicate with aircraft during the proposed instrument approach procedure, at least down to the minimum en route altitude for the controlled airspace area." 14:14:3.0.1.4.33.2.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.31 Maintenance and operations requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-2, 31 FR 5408, Apr. 6, 1966]","(a) The owner of the facility must establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility must meet at least the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility including proficiency in maintenance procedures and the use of specialized test equipment. (b) The owner must prepare, and obtain approval of, an operations and maintenance manual that sets forth mandatory procedures for operations, preventive maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons only. (3) FCC licensing requirements for operating and maintenance personnel. (4) Posting of licenses and signs. (5) Relations between the facility and FAA air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information (if applicable), and instructions for the operation of an air traffic advisory service if the facility is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed arrangements for maintenance flight inspection and servicing stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of FAA manuals by reference. (9) Keeping of station logs and other technical reports, and the submission of reports required by § 171.33. (10) Monitoring of the facility, at least once each half hour, to assure continuous operation. (11) Inspections by United States personnel. (12) Names, addresses, and telephone numbers of persons to be notified in an emergency. (13) Shutdowns for routine maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns (private use facilities may omit the “Notices to Airmen”). (14) Commissioning of the facility. (15) An acceptable procedure for amending or revising the manual. (16) The following information concerning the facility: (i) Location by latitude and longitude to the nearest second, and its position with respect to airport layouts. (ii) The type, make, and model of the basic radio equipment that will provide the service. (iii) The station power emission and frequency. (iv) The hours of operation. (v) Station identification call letters and method of station identification, whether by Morse code or recorded voice announcement, and the time spacing of the identification. (c) If the owner desires to modify the facility, he must submit the proposal to the FAA and meet applicable requirements of the FCC. (d) The owner's maintenance personnel must participate in initial inspections made by the FAA. In the case of subsequent inspections, the owner or his representative shall participate. (e) The owner shall provide a stock of spare parts, including vacuum tubes, of such a quantity to make possible the prompt replacement of components that fail or deteriorate in service. (f) The owner shall close the facility upon receiving two successive pilot reports of its malfunctioning." 14:14:3.0.1.4.33.2.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,B,Subpart B—Nondirectional Radio Beacon Facilities,,§ 171.33 Reports.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-10, 40 FR 36110, Aug. 19, 1975]","The owner of each facility to which this subpart applies shall make the following reports, at the times indicated, to the FAA Regional office for the area in which the facility is located: (a) Record of meter readings and adjustments ( Form FAA-198 ). To be filled out by the owner or his maintenance representative with the equipment adjustments and meter readings as of the time of commissioning, with one copy to be kept in the permanent records of the facility and two copies to the appropriate Regional Office of the FAA. The owner shall revise the form after any major repair, modernization, or returning, to reflect an accurate record of facility operation and adjustment. (b) Facility maintenance log ( FAA Form 6030-1 ). This form is a permanent record of all equipment malfunctioning met in maintaining the facility, including information on the kind of work and adjustments made, equipment failures, causes (if determined), and corrective action taken. The owner shall keep the original of each report at the facility and send a copy to the appropriate Regional Office of the FAA at the end of the month in which it is prepared. (c) Radio equipment operation record ( Form FAA-418 ). To contain a complete record of meter readings, recorded on each scheduled visit to the facility. The owner shall keep the original of each month's record at the facility and send a copy of it to the appropriate Regional Office of the FAA." 14:14:3.0.1.4.33.3.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.41 Scope.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-2, 31 FR 5408, Apr. 6, 1966; Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]",This subpart sets forth minimum requirements for the approval and operation of non-Federal Instrument Landing System (ILS) Facilities that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. 14:14:3.0.1.4.33.3.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.43 Requests for IFR procedure.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-7, 35 FR 12711, Aug. 11, 1970]","(a) Each person who requests an IFR procedure based on an ILS facility that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of § 171.47 and is installed in accordance with § 171.49. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and a maintenance manual that meets the requirements of § 171.51. (4) A statement of intent to meet the requirements of this subpart. (5) A showing that the facility has an acceptable level of operational reliability and an acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this subparagraph. (b) After the FAA inspects and evaluates the facility, it advises the owner of the results and of any required changes in the facility or the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the facility for an in-service evaluation by the FAA." 14:14:3.0.1.4.33.3.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.45 Minimum requirements for approval.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-6, 35 FR 10288, June 24, 1970]","(a) The following are the minimum requirements that must be met before the FAA will approve an IFR procedure for a non-Federal Instrument Landing System: (1) The facility's performance, as determined by air and ground inspection, must meet the requirements of § 171.47. (2) The installation of the equipment must meet the requirements of § 171.49. (3) The owner must agree to operate and maintain the facility in accord- ance with § 171.51. (4) The owner must agree to furnish periodic reports, as set forth in § 171.53 and agree to allow the FAA to inspect the facility and its operation whenever necessary. (5) The owner must assure the FAA that he will not withdraw the facility from service without the permission of the FAA. (6) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspections made before the facility is commissioned, except that the Federal Aviation Administration may bear certain of these costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the FAA commissions the facility as a prerequisite to its approval for use in an IFR procedure. The approval is withdrawn at any time the facility does not continue to meet those requirements. In addition, the facility may be de-commissioned whenever the frequency channel is needed for higher priority common system service." 14:14:3.0.1.4.33.3.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.47 Performance requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1974, as amended by Amdt. 171-9, 38 FR 28557, Oct. 15, 1973]","(a) The Instrument Landing System must perform in accordance with the “International Standards and Recommended Practices, Aeronautical Telecommunications, Part I, Paragraph 3.1” (Annex 10 to the Convention on International Civil Aviation) except as follows: (1) The first part of paragraph 3.1.3, relating to suppression of radiation wholly or in part in any or all directions outside the 20-degree sector centered on the course line to reduce localizer does not apply. (2) Radiation patterns must conform to limits specified in 3.1.3.3 and 3.1.3.4, but this does not mean that suppression of radiation to the rear of the antenna array to satisfy difficult siting positions (as per 3.1.3.1.4) is not allowed. For example, if a reflector screen for the antenna array is required to overcome a siting problem, the area to the rear of the localizer may be made unusable and should be so advertised. (3) A third marker beacon (inner marker) is not required. (4) The frequency tolerance of the radio frequency carrier must not exceed plus or minus 0.002 percent. (b) Ground inspection consists of an examination of the design features of the equipment to determine that there will not be conditions that will allow unsafe operations because of component failure or deterioration. (c) The monitor is checked periodically, during the in-service test evaluation period, for calibration and stability. These tests, and ground checks of glide slope and localizer radiation characteristics, are conducted in accordance with FAA Handbooks AF P 6750.1 and AF P 6750.2 “Maintenance Instructions for ILS Localizer Equipment” and “Maintenance Instructions for ILS Glide Slope Equipment”. (d) Flight tests to determine the facility's adequacy for operational requirements and compliance with applicable “Standards and Recommended Practices” are conducted in accord- ance with the “U.S. Standard Flight Inspection Manual”, particularly section 217." 14:14:3.0.1.4.33.3.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.49 Installation requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-6, 35 FR 10288, June 24, 1970; Amdt. 171-16, 56 FR 65664, Dec. 17, 1991]","(a) The facility must be of a permanent nature, located, constructed, and installed according to ICAO Standards (Annex 10), accepted good engineering practices, applicable electric and safety codes, and FCC licensing requirements. (b) The facility must have a reliable source of suitable primary power, either from a power distribution system or locally generated. A determination by the Administrator as to whether a facility will be required to have stand-by power for the localizer, glide slope and monitor accessories to supplement the primary power, will be made for each airport based upon operational minimums and density of air traffic. (c) A determination by the Administrator as to whether a facility will be required to have dual transmitting equipment with automatic changeover for localizer and glide slope components, will be made for each airport based upon operational minimums and density of air traffic. (d) There must be a means for determining, from the ground, the perform- ance of the equipment (including antennae), initially and periodically. (e) The facility must have, or be supplemented by (depending on the circumstances) the following ground-air or landline communications services: (1) At facilities outside of and not immediately adjacent to controlled airspace, there must be ground-air communications from the airport served by the facility. The utilization of voice on the ILS frequency should be determined by the facility operator on an individual basis. (2) At facilities within or immediately adjacent to controlled airspace, there must be the ground-air communications required by paragraph (e)(1) of this section and reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communications facility. Paragraphs (e)(1) and (e)(2) of this section are not mandatory at airports where an adjacent FAA facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of paragraphs (e)(1) and (e)(2) of this section may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest FAA air traffic control or communications facility, if an adjacent FAA facility can communicate with aircraft during the proposed instrument approach procedure down to the airport surface or at least to the minimum approach altitude." 14:14:3.0.1.4.33.3.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.51 Maintenance and operations requirements.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-2, 31 FR 5408, Apr. 6, 1966]","(a) The owner of the facility must establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility must meet at least the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility including proficiency in maintenance procedures and the use of specialized test equipment. (b) The owner must prepare, and obtain approval of, an operations and maintenance manual that sets forth mandatory procedures for operations, preventive maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons only. (3) FCC licensing requirements for operating and maintenance personnel. (4) Posting of licenses and signs. (5) Relation between the facility and FAA air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information (if applicable), and instructions for the operations of an air traffic advisory service if the facility is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed and specific maintenance procedures and servicing guides stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of FAA manuals by reference. (9) Keeping of station logs and other technical reports, and the submission of reports required by § 171.53. (10) Monitoring of the facility. (11) Inspections by United States personnel. (12) Names, addresses, and telephone numbers of persons to be notified in an emergency. (13) Shutdowns for routine maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns (private use facilities may omit the “Notices to Airmen”). (14) Commissioning of the facility. (15) An acceptable procedure for amending or revising the manual. (16) An explanation of the kinds of activities (such as construction or grading) in the vicinity of the facility that may require shutdown or recertification of the facility by FAA flight check. (17) Procedures for conducting a ground check or localizer course alignment width, and clearance, and glide slope elevation angle and width. (18) The following information concerning the facility: (i) Facility component locations with respect to airport layout, instrument runway, and similar areas. (ii) The type, make, and model of the basic radio equipment that will provide the service. (iii) The station power emission and frequencies of the localizer, glide slope, markers, and associated compass locators, if any. (iv) The hours of operation. (v) Station identification call letters and method of station identification and the time spacing of the identification. (vi) A description of the critical parts that may not be changed, adjusted, or repaired without an FAA flight check to confirm published operations. (c) The owner shall make a ground check of the facility each month in accordance with procedures approved by the FAA at the time of commissioning, and shall report the results of the checks as provided in § 171.53. (d) If the owner desires to modify the facility, he must submit the proposal to the FAA and may not allow any modifications to be made without specific approval. (e) “The owner's maintenance personnel must participate in initial inspections made by the FAA. In the case of subsequent inspections, the owner or his representative shall participate.” (f) Whenever it is required by the FAA, the owner shall incorporate improvements in ILS maintenance brought about by progress in the state of the art. In addition, he shall provide a stock of spare parts, including vacuum tubes, of such a quantity to make possible the prompt replacement of components that fail or deteriorate in service. (g) The owner shall provide FAA approved test instruments needed for maintenance of the facility. (h) The owner shall close the facility upon receiving two successive pilot reports of its malfunctioning." 14:14:3.0.1.4.33.3.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,C,Subpart C—Instrument Landing System (ILS) Facilities,,§ 171.53 Reports.,FAA,,,"[Docket 5034, 29 FR 11337, Aug. 6, 1964, as amended by Amdt. 171-5, 34 FR 15245, Sept. 30, 1969; Amdt. 171-10, 40 FR 36110, Aug. 19, 1975]","The owner of each facility to which this subpart applies shall make the following reports, at the times indicated, to the FAA Regional Office for the area in which the facility is located: (a) Record of meter readings and adjustments ( Form FAA-198 ). To be filled out by the owner or his maintenance representative with the equipment adjustments and meter readings as of the time of commissioning, with one copy to be kept in the permanent records of the facility and two copies to the appropriate Regional Office of the FAA. The owner shall revise the form after any major repair, modernization, or retuning, to reflect an accurate record of facility operation and adjustment. (b) Facility maintenance log ( FormFAA 6030-1 ). This form is a permanent record of all equipment malfunctioning met in maintaining the facility, including information on the kind of work and adjustments made, equipment failures, causes (if determined), and corrective action taken. The owner shall keep the original of each report at the facility and send a copy to the appropriate Regional Office of the FAA at the end of each month in which it is prepared. (c) Radio equipment operation record ( Form FAA-418 ). To contain a complete record of meter readings, recorded on each scheduled visit to the facility. The owner shall keep the original of each month's record at the facility and send a copy of it to the appropriate Regional Office of the FAA." 14:14:3.0.1.4.33.4.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,D,Subpart D—True Lights,,§ 171.61 Air navigation certificate: Revocation and termination.,FAA,,,"[Amdt. 171-4, 33 FR 12545, Sept. 5, 1968]","(a) Except as provided in paragraph (b) of this section, each air navigation certificate of “Lawful Authority to Operate a True Light” is hereby revoked, and each application therefor is hereby terminated. (b) Paragraph (a) of this section does not apply to— (1) A certificate issued to a Federal-Aid Airport Program sponsor who was required to apply for that certificate under regulations then in effect, and who has not surrendered that certificate under § 151.86(e) of this chapter; or (2) An application made by a Federal-Aid Airport Program sponsor who was required to make that application under regulations then in effect, and who has not terminated that application under § 151.86(e) of this chapter." 14:14:3.0.1.4.33.5.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,E,Subpart E—General,,§ 171.71 Materials incorporated by reference.,FAA,,,"[Amdt. 171-8, 36 FR 5584, Mar. 25, 1971]","Copies of standards, recommended practices and documents incorporated by reference in this part are available for the use of interested persons at any FAA Regional Office and FAA Headquarters. An historical file of these materials is maintained at Headquarters, Federal Aviation Administration, 800 Independence Avenue SW., Washington, DC 20590." 14:14:3.0.1.4.33.5.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,E,Subpart E—General,,§ 171.73 Alternative forms of reports.,FAA,,,"[Amdt. 171-5, 34 FR 15245, Sept. 30, 1969, as amended by Amdt. 171-15, 54 FR 39296, Sept. 25, 1989]","On a case-by-case basis, a Regional Administrator may accept any report in a format other than the FAA form required by this part if he is satisfied that the report contains all the information required on the FAA form and can be processed by FAA as conveniently as the FAA form." 14:14:3.0.1.4.33.5.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,E,Subpart E—General,,§ 171.75 Submission of requests.,FAA,,,"[Amdt. 171-7, 35 FR 12711, Aug. 11, 1970, as amended by Amdt. 171-15, 54 FR 39296, Sept. 25, 1989]","(a) Requests for approval of facilities not having design and operational characteristics identical to those of facilities currently approved under this part, including requests for deviations from this part for such facilities, must be submitted to the Director, Advanced Systems Design Service. (b) The following requests must be submitted to the Regional Administrator of the region in which the facility is located: (1) Requests for approval of facilities that have design and operational characteristics identical to those of facilities currently approved under this part, including requests for deviations from this part for such facilities. (2) Requests for deviations from this part for facilities currently approved under this part. (3) Requests for modification of facilities currently approved under this part." 14:14:3.0.1.4.33.6.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.101 Scope.,FAA,,,,This subpart sets forth minimum requirements for the approval and operation of non-Federal Simplified Directional Facilities (SDF) that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. 14:14:3.0.1.4.33.6.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.103 Requests for IFR procedure.,FAA,,,,"(a) Each person who requests an IFR procedure based on an SDF that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of § 171.109 and the standards and tolerances of § 171.111, and is installed in accordance with § 171.113. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and a maintenance manual that meets the requirements of § 171.115. (4) A statement of intent to meet the requirements of this subpart. (5) A showing that the facility has an acceptable level of operational reliability as prescribed in § 171.111(k), and an acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this paragraph. (b) After the Federal Aviation Administration inspects and evaluates the facility, it advises the owner of the results and of any required changes in the facility or the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the facility for an in-service evaluation by the Federal Aviation Administration." 14:14:3.0.1.4.33.6.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.105 Minimum requirements for approval.,FAA,,,,"(a) The following are the minimum requirements that must be met before the Federal Aviation Administration will approve an IFR procedure for a non-Federal Simplified Directional Facility: (1) A suitable frequency channel must be available. (2) The facility's performance, as determined by air and ground inspection, must meet the requirements of §§ 171.109 and 171.111. (3) The installation of the equipment must meet the requirements of § 171.113. (4) The owner must agree to operate and maintain the facility in accordance with § 171.115. (5) The owner must agree to furnish periodic reports as set forth in § 171.117, and agree to allow the FAA to inspect the facility and its operation whenever necessary. (6) The owner must assure the FAA that he will not withdraw the facility from service without the permission of the FAA. (7) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspections made before the facility is commissioned, except that the FAA may bear certain of these costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the FAA commissions the facility as a prerequisite to its approval for use in an IFR procedure. The approval is withdrawn at any time the facility does not continue to meet those requirements. In addition, the facility is licensed by the Federal Communications Commission. The Federal Aviation Administration recommends cancellation or nonrenewal of the Federal Communications Commission license whenever the frequency channel is needed for higher priority common system service." 14:14:3.0.1.4.33.6.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.107 Definition.,FAA,,,,"As used in this subpart: SDF (simplified directional facility) means a directional aid facility providing only lateral guidance (front or back course) for approach from a final approach fix. DDM (difference in depth of modulation) means the percentage modulation depth of the larger signal minus the percentage modulation depth of the smaller signal, divided by 100. Angular displacement sensitivity means the ratio of measured DDM to the corresponding angular displacement from the appropriate reference line. Back course sector means the course sector on the opposite end of the runway from the front course sector. Course line means the locus of points along the final approach course at which the DDM is zero. Course sector means a sector in a horizontal plane containing the course line and limited by the loci of points nearest to the course line at which the DDM is 0.155. Displacement sensitivity means the ratio of measured DDM to the corresponding lateral displacement from the appropriate reference line. Front course sector means the course sector centered on the course line in the direction from the runway in which a normal final approach is made. Half course sector means the sector in a horizontal plane containing the course line and limited by the loci of points nearest to the course line, at which the DDM is 0.0775. Point A means a point on the front course in the approach direction a distance of 4 nautical miles from the threshold. Point A1 means a point on the front course in the approach direction a distance of 1 statute mile from the threshold. Point A2 means a point on the front course at the threshold. Reference datum means a point at a specified height located vertically above the intersection of the course and the threshold. Missed approach point means the point on the final approach course, not farther from the final approach fix than Point “A2”, at which the approach must be abandoned, if the approach and subsequent landing cannot be safely completed by visual reference, whether or not the aircraft has descended to the minimum descent altitude." 14:14:3.0.1.4.33.6.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.109 Performance requirements.,FAA,,,"[Docket 10116, 35 FR 12711, Aug. 11, 1970, as amended by Amdt. 171-9, 38 FR 28557, Oct. 15, 1973]","(a) The Simplified Directional Facility must perform in accordance with the following standards and practices: (1) The radiation from the SDF antenna system must produce a composite field pattern which is amplitude modulated by a 90 Hz and a 150 Hz tone. The radiation field pattern must produce a course sector with the 90 Hz tone predominating on one side of the course and with the 150 Hz tone predominating on the opposite side. (2) When an observer faces the SDF from the approach end of runway, the depth of modulation of the radio frequency carrier due to the 150 Hz tone must predominate on his right hand and that due to the 90 Hz tone must predominate on his left hand. (3) All horizontal angles employed in specifying the SDF field patterns must originate from the center of the antenna system which provides the signals used in the front course sector. (4) The SDF must operate on odd tenths or odd tenths plus a twentieth MHz within the frequency band 108.1 MHz to 111.95 MHz. The frequency tolerance of the radio frequency carrier must not exceed plus or minus 0.002 percent. (5) The radiated emission from the SDF must be horizontally polarized. The vertically polarized component of the radiation on the course line must not exceed that which corresponds to an error one-twentieth of the course sector width when an aircraft is positioned on the course line and is in a roll attitude of 20° from the horizontal. (6) The SDF must provide signals sufficient to allow satisfactory operation of a typical aircraft installation within the sector which extends from the center of the SDF antenna system to distances of 18 nautical miles within a plus or minus 10° sector and 10 nautical miles within the remainder of the coverage when alternative navigational facilities provide satisfactory coverage within the intermediate approach area. SDF signals must be receivable at the distances specified at and above a height of 1,000 feet above the elevation of the threshold, or the lowest altitude authorized for transition, whichever is higher. Such signals must be receivable, to the distances specified, up to a surface extending outward from the SDF antenna and inclined at 7° above the horizontal. (7) The modulation tones must be phase-locked so that within the half course sector, the demodulated 90 Hz and 150 Hz wave forms pass through zero in the same direction within 20° of phase relative to the 150 Hz component, every half cycle of the combined 90 Hz and 150 Hz wave form. However, the phase need not be measured within the half course sector. (8) The angle of convergence of the final approach course and the extended runway centerline must not exceed 30°. The final approach course must be aligned to intersect the extended runway centerline between points A1 and the runway threshold. When an operational advantage can be achieved, a final approach course that does not intersect the runway or that intersects it at a distance greater than point A1 from the threshold, may be established, if that course lies within 500 feet laterally of the extended runway centerline at a point 3,000 feet outward from the runway threshold. The mean course line must be maintained within ±10 percent of the course sector width. (9) The nominal displacement sensitivity within the half course sector must be 50 microamperes/degree. The nominal course sector width must be 6°. When an operational advantage can be achieved, a nominal displacement sensitivity of 25 microamperes/degree may be established, with a nominal course sector width of 12° with proportional displacement sensitivity. The lateral displacement sensitivity must be adjusted and maintained within the limits of plus or minus 17 percent of the nominal value. (10) The off-course (clearance) signal must increase at a substantially linear rate with respect to the angular displacement from the course line up to an angle on either side of the course line where 175 microamperes of deflection is obtained. From that angle to ±10°, the off-course deflection must not be less than 175 microamperes. From ±10° to ±35° the off-course deflection must not be less than 150 microamperes. With the course adjusted to cause any of several monitor alarm conditions, the aforementioned values of 175 microamperes in the sector 10° each side of course and 150 microamperes in the sector ±10° to ±35° may be reduced to 160 microamperes and 135 microamperes, respectively. These conditions must be met at a distance of 18 nautical miles from the SDF antenna within the sector 10° each side of course line and 10 nautical miles from the SDF antenna within the sector ±10° to ±35° each side of course line. (11) The SDF may provide a ground-to-air radiotelephone communication channel to be operated simultaneously with the navigation and identification signals, if that operation does not interfere with the basic function. If a channel is provided, it must conform with the following standards: (i) The channel must be on the same radio frequency carrier or carriers as used for the SDF function, and the radiation must be horizontally polarized. Where two carriers are modulated with speech, the relative phases of the modulations on the two carriers must avoid the occurrence of nulls within the coverage of the SDF. (ii) On centerline, the peak modulation depth of the carrier or carriers due to the radiotelephone communications must not exceed 50 percent but must be adjusted so that the ratio of peak modulation depth due to the radiotelephone communications to that due to the identification signal is approximately 9:1. (iii) The audio frequency characteristics of the radiotelephone channel must be flat to within 3 db relative to the level at 1,000 Hz over the range from 300 Hz to 3,000 Hz. (12)(i) The SDF must provide for the simultaneous transmission of an identification signal, specific to the runway and approach direction, on the same radio frequency carrier or carriers as used for the SDF function. The transmission of the identification signal must not interfere in any way with the basic SDF function. (ii) The identification signal must be produced by Class A2 modulation of the radio frequency carrier or carriers using a modulation tone of 1020 Hz within ±50 Hz. The depth of modulation must be between the limits of 5 and 15 percent except that, where a radiotelephone communication channel is provided, the depth of modulation must be adjusted so that the ratio of peak modulation depth due to radiotelephone communications to that due to the identification signal modulation is approximately 9:1. The emissions carrying the identification signal must be horizontally polarized. (iii) The identification signal must employ the International Morse Code and consist of three letters. (iv) The identification signal must be transmitted at a speed corresponding to approximately seven words per minute, and must be repeated at approximately equal intervals, not less than six times per minute. When SDF transmission is not available for operational use, including periods of removal of navigational components or during maintenance or test transmissions, the identification signal must be suppressed. (b) It must be shown during ground inspection of the design features of the equipment that there will not be conditions that will allow unsafe operations because of component failure or deterioration. (c) The monitor must be checked periodically during the in-service test evaluation period for calibration and stability. These tests, and ground checks of SDF radiation characteristics must be conducted in accordance with the maintenance manual required by § 171.115(c) and must meet the standards and tolerances contained in § 171.111(j). (d) The monitor system must provide a warning to the designated control point(s) when any of the conditions of § 171.111(j) occur, within the time periods specified in that paragraph. (e) Flight inspection to determine the adequacy of the facility's operational performance and compliance with applicable performance requirements must be conducted in accordance with the “U.S. Standard Flight Inspection Manual.” Tolerances contained in the U.S. Standard Flight Inspection Manual, section 217, must be complied with except as stated in paragraph (f) of this section. (f) Flight inspection tolerances specified in section 217 of the “U.S. Standard Flight Inspection Manual” must be complied with except as follows: (1) Course sector width. The nominal course sector width must be 6°. When an operational advantage can be achieved, a nominal course sector width of 12° may be established. Course sector width must be adjusted and maintained within the limits of ±17 percent of the nominal value. (2) Course alignment. The mean course line must be adjusted and maintained within the limits of ±10 percent of the nominal course sector width. (3) Course structure. Course deviations due to roughness, scalloping, or bends must be within the following limitations: (i) Front course. ( a ) Course structure from 18 miles from runway threshold to Point A must not exceed ±40 microamperes; ( b ) Point A to Point A-1—linear decrease from not more than ±40 microamperes at Point A to not more than ±20 microamperes at Point A-1; ( c ) Point A-1 to Missed Approach Point—not more than ±20 microamperes; ( d ) Monitor tolerances: width ±17 percent of nominal; alignment—±10 percent of nominal course sector width. (ii) Back course. ( a ) Course structure 18 miles from runway threshold to 4 miles from runway threshold must not exceed ±40 microamperes. Four miles to 1 mile from R/W must not exceed ±40 microamperes decreasing to not more than ±20 microamperes, at a linear rate. ( b ) Monitor tolerances: width—±17 percent of nominal; alignment—±10 percent of nominal course sector width." 14:14:3.0.1.4.33.6.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.111 Ground standards and tolerances.,FAA,,,"[Docket 10116, 35 FR 12711, Aug. 11, 1970, as amended by Amdt. 171-9, 38 FR 28558, Oct. 15, 1973]","Compliance with this section must be shown as a condition to approval and must be maintained during operation of the SDF. (a) Frequency. (1) The SDF must operate on odd tenths or odd tenths plus a twentieth MHz within the frequency band 108.1 MHz to 111.95 MHz. The frequency tolerance of the radio frequency carrier must not exceed plus or minus 0.002 percent. (2) The modulating tones must be 90 Hz and 150 Hz within ±2.5 percent. (3) The identification signal must be 1020 Hz within ±50 Hz. (4) The total harmonic content of the 90 Hz tone must not exceed 10 percent. (5) The total harmonic content of the 150 Hz tone must not exceed 10 percent. (b) Power output. The normal carrier power output must be of a value which will provide coverage requirements of § 171.109(a)(6) when reduced by 3 dB to the monitor RF power reduction alarm point specified in § 171.111(j)(3). (c) VSWR. (1) The VSWR of carrier and sideband feedlines must be a nominal value of 1/1 and must not exceed 1.2/1. (2) The sponsor will also provide additional manufacturer's ground standards and tolerances for all VSWR parameters peculiar to the equipment which can effect performance of the facility in meeting the requirements specified in §§ 171.109 and 171.111. (d) Insulation resistance. The insulation resistance of all coaxial feedlines must be greater than 20 megohms. (e) Depth of modulation. (1) The depth of modulation of the radio frequency carrier due to each of the 90 Hz and 150 Hz tones must be 20 percent ±2 percent along the course line. (2) The depth of modulation of the radio frequency carrier due to the 1020 Hz identification signal must be within 5 percent to 15 percent. (f) Course sector width. The standard course sector width must be 6° or 12°. The course sector must be maintained with ±17 percent of the standard. (g) Course alignment. Course alignment must be as specified in § 171.109(a)(8). (h) Back course alignment and width. If a back course is provided, standards and tolerances for back course sector width and alignment must be the same as course sector width and course alignment specified in paragraphs (f) and (g) of this section. (i) Clearance. Clearance must be as specified in § 171.109(a)(10). (j) Monitor standards and tolerances. (1) The monitor system must provide a warning to the designated control point(s) when any of the conditions described in this paragraph occur, within the time periods specified in paragraph (j)(6) of this section. (2) Course shift alarm: The monitor must alarm and cause radiation to cease, or identification and navigation signals must be removed, if the course alignment deviates from standard alignment by 10 percent or more of the standard course sector width. (3) RF power reduction alarm: The monitor must alarm and cause radiation to cease, or identification and navigation signals must be removed, if the output power is reduced by 3 db or more from normal. (4) Modulation level alarm: The monitor must alarm and cause radiation to cease, or identification and navigation signals must be removed, if the 90 Hz and 150 Hz modulation levels decrease by 17 percent or more. (5) Course sector width alarm: The monitor must alarm and cause radiation to cease, or identification and navigation signals must be removed, for a change in course sector width to a value differing by ±17 percent or more from the standard. (6) Monitor delay before shutdown: Radiation must cease, or identification and navigation signals must be removed, within 10 seconds after a fault is detected by the monitor, and no attempt must be made to resume radiation for a period of at least 20 seconds. If an automatic recycle device is used, not more than three successive recycles may be permitted before a complete SDF shutdown occurs. (k) Mean time between failures. The mean time between failures must not be less than 800 hours. This measure is applied only to equipment failures (monitor or transmitting equipment, including out of tolerance conditions) which result in facility shutdown. It does not relate to the responsiveness of the maintenance organization. (l) Course alignment stability. Drift of the course alignment must not exceed one-half the monitor limit in a 1-week period." 14:14:3.0.1.4.33.6.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.113 Installation requirements.,FAA,,,"[Docket 10116, 35 FR 12711, Aug. 11, 1970, as amended by Amdt. 171-16, 56 FR 65664, Dec. 17, 1991]","(a) The facility must be installed according to accepted good engineering practices, applicable electric and safety codes, and FCC requirements. (b) The SDF facility must have the following basic components: (1) VHF SDF equipment and associated monitor system; (2) Remote control, and indicator equipment (remote monitor) when required by the FAA; (3) A final approach fix; and (4) Compass locator (COMLO) or marker if suitable fixes and initial approach routes are not available from existing facilities. (c) The facility must have a reliable source of suitable primary power, either from a power distribution system or locally generated. Also, adequate power capacity must be provided for operation of test and working equipment at the SDF. A determination by the Federal Aviation Administration as to whether a facility will be required to have standby power for the SDF and monitor accessories to supplement the primary power will be made for each airport based upon operational minimums and density of air traffic. (d) A determination by the Federal Aviation Administration as to whether a facility will be required to have dual transmitting equipment with automatic changeover for the SDF will be made for each airport based upon operational minimums and density of air traffic. (e) There must be a means for determining, from the ground, the performance of the equipment (including antennae), initially and periodically. (f) The facility must have the following ground-air or landline communication services: (1) At facilities outside of and not immediately adjacent to controlled airspace, there must be ground-air communications from the airport served by the facility. The utilization of voice on the SDF should be determined by the facility operator on an individual basis. (2) At facilities within or immediately adjacent to controlled airspace, there must be ground/air communications required by paragraph (b)(1) of this section and reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communications facility. Compliance with paragraphs (f) (1) and (2) of this section need not be shown at airports where an adjacent Federal Aviation Administration facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of paragraphs (f) (1) and (2) of this section may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communications facility, if an adjacent Federal Aviation Administration facility can communicate with aircraft during the proposed instrument approach procedure down to the airport surface or at least down to the minimum approach altitude. (g) At those locations where two separate SDF facilities serve opposite ends of a single runway, an interlock must insure that only the facility serving the approach direction in use can radiate, except where no operationally harmful interference results. (h) At those locations where, in order to alleviate frequency congestion, the SDF facilities serving opposite ends of one runway employ identical frequencies, an interlock must insure that the facility not in operational use cannot radiate. (i) Provisions for maintenance and operations by authorized persons only. (j) Where an operational advantage exists, the installation may omit a back course." 14:14:3.0.1.4.33.6.3.8,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.115 Maintenance and operations requirements.,FAA,,,,"(a) The owner of the facility shall establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility shall meet at a minimum the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility, including proficiency in maintenance procedures and the use of specialized test equipment. (b) The SDF must be designed and maintained so that the probability of operation within the performance requirements specified is high enough to insure an adequate level of safety. In the event out-of-tolerance conditions develop, the facility shall be removed from operation, and the designated control point notified. (c) The owner must prepare, and obtain approval of, and each person operating or maintaining the facility shall comply with, an operations and maintenance manual that sets forth procedures for operations, preventive maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. This includes provisions for designating critical areas relative to the facility and preventing or controlling movements within the facility that may adversely affect SDF operations. (2) Maintenance and operations by authorized persons only. (3) Federal Communications Commission requirements for operating personnel and maintenance personnel. (4) Posting of licenses and signs. (5) Relation between the facility and Federal Aviation Administration air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information (if applicable), and instructions for the operation of an air traffic advisory service if the facility is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed and specific maintenance procedures and servicing guides stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of Federal Aviation Administration manuals by reference. (9) Keeping of station logs and other technical reports, and the submission of reports required by § 171.117. (10) Monitoring of the facility. (11) Names, addresses, and telephone numbers of persons to be notified in an emergency. (12) Inspection by U.S. personnel. (13) Shutdowns for routine maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns, except that private use facilities may omit “Notices to Airmen.” (14) Commissioning of the facility. (15) An acceptable procedure for amending or revising the manual. (16) An explanation of the kinds of activities (such as construction or grading) in the vicinity of the facility that may require shutdown or certification of the facility by Federal Aviation Administration flight check. (17) Procedure for conducting a ground check of SDF course alignment, width and clearance. (18) The following information concerning the facility: (i) Facility component locations with respect to airport layout, instrument runway, and similar areas; (ii) The type, make, and model of the basic radio equipment that will provide the service; (iii) The station power emission and frequencies of the SDF, markers and associated COMLOs, if any; (iv) The hours of operation; (v) Station identification call letters and method of station identification and the time spacing of the identification; (vi) A description of the critical parts that may not be changed, adjusted, or repaired without a Federal Aviation Administration flight check to confirm published operations. (d) The owner shall make a ground check of the facility each month in accordance with procedures approved by the Federal Aviation Administration at the time of commissioning, and shall report the results of the checks as provided in § 171.117. (e) If the owner desires to modify the facility, he shall submit the proposal to the Federal Aviation Administration and may not allow any modifications to be made without specific approval. (f) The owner's maintenance personnel shall participate in initial inspections made by the Federal Aviation Administration. In the case of subsequent inspections, the owner or his representatives shall participate. (g) Whenever it is required by the Federal Aviation Administration, the owner shall incorporate improvements in SDF maintenance. In addition, he shall provide a stock of spare parts, of such a quantity, to make possible the prompt replacement of components that fail or deteriorate in service. (h) The owner shall provide Federal Aviation Administration approved test instruments needed for maintenance of the facility. (i) The owner shall close the facility by ceasing radiation and shall issue a “Notice to Airmen” that the facility is out of service (except that private use facilities may omit “Notices to Airmen”), upon receiving two successive pilot reports of its malfunctioning." 14:14:3.0.1.4.33.6.3.9,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,F,Subpart F—Simplified Directional Facility (SDF),,§ 171.117 Reports.,FAA,,,"[Docket 10116, 35 FR 12711, Aug. 11, 1970, as amended by Amdt. 171-10, 40 FR 36110, Aug. 19, 1975]","The owner of each facility to which this subpart applies shall make the following reports, at the time indicated, to the Federal Aviation Administration Regional Office for the area in which the facility is located: (a) Record of meter readings and adjustments (Form FAA-198). To be filled out by the owner or his maintenance representative with the equipment adjustments and meter readings as of the time of commissioning, with one copy to be kept in the permanent records of the facility and two copies to the appropriate Regional Office of the Federal Aviation Administration. The owner shall revise the form after any major repair, modification, or retuning, to reflect an accurate record of facility operation and adjustment. (b) Facility maintenance log (FAA Form 6030-1) This form is a permanent record of all equipment malfunctioning met in maintaining the facility, including information on the kind of work and adjustments made, equipment failures, causes (if determined), and corrective action taken. The owner shall keep the original of each report at the facility and send a copy to the appropriate Regional Office of the Federal Aviation Administration at the end of each month in which it is prepared. (c) Radio equipment operation record (Form FAA-418), containing a complete record of meter readings, recorded on each scheduled visit to the facility. The owner shall keep the original of each month's record at the facility and send a copy of it to the appropriate Regional Office of the Federal Aviation Administration." 14:14:3.0.1.4.33.7.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.151 Scope.,FAA,,,,This subpart sets forth minimum requirements for the approval and operation of non-Federal DME facilities that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. 14:14:3.0.1.4.33.7.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.153 Requests for IFR procedure.,FAA,,,,"(a) Each person who requests an IFR procedure based on a DME facility that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of § 171.157 and is installed in accordance with § 171.159. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and maintenance manual that meets the requirement of § 171.161. (4) A statement of intention to meet the requirements of this subpart. (5) A showing that the facility has an acceptable level of operational reliability and an acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this paragraph. (b) After the Federal Aviation Administration inspects and evaluates the facility, it advises the owner of the results and of any required changes in the facility or the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the facility for an in-service evaluation by the Federal Aviation Administration." 14:14:3.0.1.4.33.7.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.155 Minimum requirements for approval.,FAA,,,,"(a) The following are the minimum requirements that must be met before the Federal Aviation Administration will approve an IFR procedure for a non-Federal DME: (1) A suitable frequency channel must be available. (2) The facility's performance, as determined by air and ground inspection, must meet the requirements of § 171.157. (3) The installation of the equipment must meet the requirements of § 171.159. (4) The owner must agree to operate and maintain the facility in accordance with § 171.161. (5) The owner must agree to furnish periodic reports, as set forth in § 171.163, and must agree to allow the Federal Aviation Administration to inspect the facility and its operation whenever necessary. (6) The owner must assure the Federal Aviation Administration that he will not withdraw the facility from service without the permission of the Federal Aviation Administration. (7) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspections made before the facility is commissioned, except that the Federal Aviation Administration may bear certain of these costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the Federal Aviation Administration commissions the facility as a prerequisite to its approval for use in an IFR procedure. The approval is withdrawn at any time the facility does not continue to meet those requirements." 14:14:3.0.1.4.33.7.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.157 Performance requirements.,FAA,,,"[Docket 10116, 35 FR 12715, Aug. 11, 1970, as amended by Amdt. 171-13, 50 FR 4875, Nov. 27, 1985]","(a) The DME must meet the performance requirements set forth in the “International Standards and Recommended Practices. Aeronautical Telecommunications, Part I, Paragraph 3.5” (Annex 10 to the Convention of International Civil Aviation). (b) It must be shown during ground inspection of the design features of the equipment that there will not be conditions that will allow unsafe operations because of component failure or deterioration. (c) The monitor must be checked periodically, during the in-service test evaluation period, for calibration and stability. These tests and ground tests of the functional and performance characteristics of the DME transponder must be conducted in accordance with the maintenance manual required by § 171.161(b). (d) Flight inspection to determine the adequacy of the facility's operational performance and compliance with applicable “Standards and Recommended Practices” must be accomplished in accordance with the “U.S. Standard Flight Inspection Manual.”" 14:14:3.0.1.4.33.7.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.159 Installation requirements.,FAA,,,"[Docket 10116, 35 FR 12715, Aug. 11, 1970, as amended by Amdt. 171-16, 56 FR 65665, Dec. 17, 1991]","(a) The facility must be installed according to accepted good engineering practices, applicable electric and safety codes, and Federal Communications Commission requirements. (b) The facility must have a reliable source of suitable primary power, either from a power distribution system or locally generated, with a supplemental standby system, if needed. (c) Dual transmitting equipment with automatic changeover is preferred and may be required to support certain IFR procedures. (d) There must be a means for determining from the ground, the performance of the equipment, initially and periodically. (e) A facility intended for use as an instrument approach aid for an airport must have or be supplemented by the following ground air or landline communications services: (1) At facilities outside of and not immediately adjacent to controlled airspace, there must be ground-air communications from the airport served by the facility. Separate communications channels are acceptable. (2) At facilities within or immediately adjacent to controlled airspace, there must be the ground-air communications required by paragraph (e)(1) of this section and reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communications facility. Separate communications channels are acceptable. Compliance with paragraphs (e) (1) and (2) of this section need not be shown at airports where an adjacent Federal Aviation Administration facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of paragraphs (e) (1) and (2) of this section may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communications facility, if an adjacent Federal Aviation Administration facility can communicate with aircraft during the proposed instrument approach procedure, at least down to the minimum en route altitude for the controlled airspace area." 14:14:3.0.1.4.33.7.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.161 Maintenance and operations requirements.,FAA,,,,"(a) The owner of the facility shall establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility shall meet at a minimum the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility, including proficiency in maintenance procedures and the use of specialized test equipment. (b) The owner must prepare and obtain Federal Aviation Administration approval of, and each person operating or maintaining the facility shall comply with, an operations and maintenance manual that sets forth procedures for operations, preventive maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons only. (3) Federal Communications Commission's requirements and maintenance personnel. (4) Posting of licenses and signs. (5) Relations between the facility and Federal Aviation Administration air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information (if applicable), and instructions for the operation of an air traffic advisory service if the DME is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed and specific maintenance procedures and servicing guides stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of Federal Aviation Administration manuals by reference. (9) Keeping of station logs and other technical reports, and the submission of reports required by § 171.163. (10) Monitoring of the facility. (11) Inspections by U.S. personnel. (12) Names, addresses, and telephone numbers of persons to be notified in an emergency. (13) Shutdowns for routine maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns, except that private use facilities may omit the “Notices to Airmen.” (14) An explanation of the kinds of activity (such as construction or grading) in the vicinity of the facility that may require shutdown or reapproval of the facility by Federal Aviation Administration flight check. (15) Commissioning of the facility. (16) An acceptable procedure for amending or revising the manual. (17) The following information concerning the facility: (i) Location by latitude and longitude to the nearest second, and its position with respect to airport layouts. (ii) The type, make, and model of the basic radio equipment that will provide the service. (iii) The station power emission and frequency. (iv) The hours of operation. (v) Station identification call letters and methods of station identification, whether by Morse code or recorded voice announcement, and the time spacing of the identification. (vi) A description of the critical parts that may not be changed, adjusted, or repaired without an FAA flight check to confirm published operations. (c) The owner shall make a monthly ground operational check in accordance with procedures approved by the FAA at the time of commissioning, and shall report the results of the checks as provided in § 171.163. (d) If the owner desires to modify the facility, he shall submit the proposal to the FAA and may not allow any modifications to be made without specific approval. (e) The owner's maintenance personnel shall participate in initial inspections made by the FAA. In the case of subsequent inspections, the owner or his representative shall participate. (f) Whenever it is required by the FAA, the owner shall incorporate improvements in DME maintenance. (g) The owner shall provide a stock of spare parts of such a quantity to make possible the prompt replacement of components that fail or deteriorate in service. (h) The owner shall provide FAA-approved test instruments needed for maintenance of the facility. (i) The owner shall shut down the facility ( i.e. , cease radiation and issue a NOTAM that the facility is out-of-service) upon receiving two successive pilot reports of its malfunctioning." 14:14:3.0.1.4.33.7.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,G,Subpart G—Distance Measuring Equipment (DME),,§ 171.163 Reports.,FAA,,,"[Docket 10116, 35 FR 12715, Aug. 11, 1970, as amended by Amdt. 171-10, 40 FR 36110, Aug. 19, 1975]","The owner of each facility to which this subpart applies shall make the following reports on forms furnished by the FAA, at the time indicated, to the FAA Regional office for the area in which the facility is located: (a) Record of meter readings and adjustments (Form FAA-198). To be filled out by the owner with the equipment adjustments and meter readings as of the time of commissioning, with one copy to be kept in the permanent records of the facility and two copies to the appropriate Regional office of the FAA. The owner shall revise the form after any major repair, modification, or returning, to reflect an accurate record of facility operation and adjustment. (b) Facility maintenance log (FAA Form 6030-1). This form is a permanent record of all equipment malfunctioning met in maintaining the facility, including information on the kind of work and adjustments made, equipment failures, causes (if determined), and corrective action taken. The owner shall keep the original of each report at the facility and send a copy to the appropriate Regional Office of the Federal Aviation Administration at the end of the month in which it is prepared. (c) Radio equipment operation record (Form FAA-418), containing a complete record of meter readings, recorded on each scheduled visit to the facility. The owner shall keep the original of each month's record at the facility and send a copy of it to the appropriate Regional Office of the Federal Aviation Administration." 14:14:3.0.1.4.33.8.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.201 Scope.,FAA,,,,"(a) This subpart sets forth minimum requirements for the approval and operation of non-Federal VHF marker beacon facilities that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. (b) [Reserved]" 14:14:3.0.1.4.33.8.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.203 Requests for IFR procedure.,FAA,,,,"(a) Each person who requests an IFR procedure which will incorporate the use of a VHF marker beacon facility that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of § 171.207 and is installed in accordance with § 171.209. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and a maintenance manual that meets the requirements of § 171.211. (4) A statement of intent to meet the requirement of this subpart. (5) A showing that the facility has an acceptable level of operational reliability, and an acceptable standard of performance. Previous equivalent operational experience may be shown to comply with this subparagraph. (b) After the Federal Aviation Administration inspects and evaluates the facility, it advises the owner of the results and of any required changes in the facility or the maintenance manual or maintenance organization. The owner shall then correct the deficiencies, if any, and operate the facility for an in-service evaluation by the Federal Aviation Administration." 14:14:3.0.1.4.33.8.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.205 Minimum requirements for approval.,FAA,,,,"(a) The following are the minimum requirements that must be met before the Federal Aviation Administration will approve an IFR procedure which incorporates the use of a non-Federal VHF marker beacon facility under this subpart: (1) The facility's performances, as determined by air and ground inspection, must meet the requirements of § 171.207. (2) The installation of the equipment must meet the requirements of § 171.209. (3) The owner must agree to operate and maintain the facility in accordance with § 171.211. (4) The owner must agree to furnish periodic reports, as set forth in § 171.213, and agree to allow the Federal Aviation Administration to inspect the facility and its operation whenever necessary. (5) The owner must assure the Federal Aviation Administration that he will not withdraw the facility from service without the permission of the Federal Aviation Administration. (6) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspections made before the facility is commissioned, except that the Federal Aviation Administration may bear certain of these costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the Federal Aviation Administration commissions the facility as a prerequisite to its approval for use in an IFR procedure. The approval is withdrawn at any time the facility does not continue to meet those requirements." 14:14:3.0.1.4.33.8.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.207 Performance requirements.,FAA,,,,"(a) VHF Marker Beacons must meet the performance requirements set forth in the “International Standards and Recommended Practices, Aeronautical Telecommunications, Part I, paragraphs 3.1.6 and 3.6.” (Annex 10 to the Convention on International Civil Aviation) except those portions that pertain to identification. Identification of a marker beacon (75 MHz) must be in accordance with “U.S. Standard Flight Inspection Manual,” § 219. (b) The facility must perform in accordance with recognized and accepted good electronic engineering practices for the desired service. The facility must be checked periodically during the in-service test evaluation period for calibration and stability. These tests and ground tests of the marker radiation characteristics must be conducted in accordance with the maintenance manual required by § 171.211(b). (c) It must be shown during ground inspection of the design features of the equipment that there will not be conditions that will allow unsafe operations because of component failure or deterioration. (d) Flight inspection to determine the adequacy of the facility's operational performance and compliance with applicable “Standards and Recommended Practices” are conducted in accordance with the “U.S. Standard Flight Inspection Manual.” The original test is made by the Federal Aviation Administration and later tests must be made under arrangements, satisfactory to the Federal Aviation Administration, that are made by the owner." 14:14:3.0.1.4.33.8.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.209 Installation requirements.,FAA,,,"[Docket 10116, 35 FR 12716, Aug. 11, 1970, as amended by Amdt. 171-16, 56 FR 65665, Dec. 17, 1991]","(a) The facility must be installed according to accepted good engineering practices, applicable electric and safety codes, and Federal Communications Commission requirements. (b) The facility must have a reliable source of suitable primary power. (c) Dual transmitting equipment may be required, if applicable, to support certain IFR procedures. (d) At facilities within or immediately adjacent to controlled airspace and that are intended for use as instrument approach aids for an airport, there must be ground-air communications or reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communication facility. Compliance with this paragraph need not be shown at airports where an adjacent Federal Aviation Administration facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of this paragraph may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communications facility, if an adjacent Federal Aviation Administration facility can communicate with aircraft during the proposed instrument approach procedure, at least down to the minimum en route altitude for the controlled airspace area." 14:14:3.0.1.4.33.8.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.211 Maintenance and operations requirements.,FAA,,,,"(a) The owner of the facility shall establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility shall meet at a minimum the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility, including proficiency in maintenance procedures and the use of specialized test equipment. (b) The owner must prepare, and obtain approval of, and each person who operates or maintains the facility shall comply with, an operations and maintenance manual that sets forth procedures for operations, preventive maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons only. (3) Federal Communications Commission's requirements for operating and maintenance personnel. (4) Posting of licenses and signs. (5) Relations between the facility and Federal Aviation Administration air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information (if applicable). (6) Notice to the Administrator of any suspension of service. (7) Detailed arrangements for maintenance, flight inspection, and servicing, stating the frequency of servicing. (8) Keeping of station logs and other technical reports, and the submission of reports required by § 171.213. (9) Monitoring of the facility, at least once each half hour, to assure continuous operation. (10) Inspections by U.S. personnel. (11) Names, addresses, and telephone numbers of persons to be notified in an emergency. (12) Shutdowns for routine maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns (private use facilities may omit the “Notice to Airmen”). (13) Commissioning of the facility. (14) An acceptable procedure for amending or revising the manual. (15) The following information concerning the facility: (i) Location by latitude and longitude to the nearest second, and its position with respect to airport layouts. (ii) The type, make, and model of the basic radio equipment that will provide the service. (iii) The station power emission and frequency. (iv) The hours of operation. (v) Station identification call letters and methods of station identification, whether by Morse Code or recorded voice announcement, and the time spacing of the identification. (c) If the owner desires to modify the facility, he shall submit the proposal to the Federal Aviation Administration and meet applicable requirements of the Federal Communications Commission, and must not allow any modification to be made without specific approval by the Federal Aviation Administration. (d) The owner's maintenance personnel shall participate in initial inspections made by the Federal Aviation Administration. In the case of subsequent inspections, the owner or his representative shall participate. (e) The owner shall provide a stock of spare parts, of such a quantity to make possible the prompt replacement of components that fail or deteriorate in service. (f) The owner shall shut down the facility by ceasing radiation, and shall issue a “Notice to Airmen” that the facility is out of service (except that private use facilities may omit “Notices to Airmen”) upon receiving two successive pilot reports of its malfunctioning." 14:14:3.0.1.4.33.8.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,H,Subpart H—VHF Marker Beacons,,§ 171.213 Reports.,FAA,,,"[Docket 10116, 35 FR 12716, Aug. 11, 1970, as amended by Amdt. 171-10, 40 FR 36110, Aug. 19, 1975]","The owner of each facility to which this subpart applies shall make the following reports, at the times indicated, to the Federal Aviation Administration Regional Office for the area in which the facility is located: (a) Record of meter readings and adjustments (Form FAA-198). To be filled out by the owner or his maintenance representative with the equipment adjustments and meter readings as of the time of commissioning, with one copy to be kept in the permanent records of the facility and two copies to the appropriate Regional Office of the Federal Aviation Administration. The owner must revise the form after any major repair, modification, or retuning, to reflect an accurate record of facility operation and adjustment. (b) Facility maintenance log (FAA Form 6030-1). This form is a permanent record of all equipment malfunctioning met in maintaining the facility, including information on the kind of work and adjustments made, equipment failures, causes (if determined), and corrective action taken. The owner shall keep the original of each report at the facility and send a copy to the appropriate Regional Office of the Federal Aviation Administration at the end of the month in which it is prepared. (c) Radio equipment operation record (Form FAA-418), containing a complete record of meter readings, recorded on each scheduled visit to the facility. The owner shall keep the original of each month's record at the facility and send a copy of it to the appropriate Regional Office of the Federal Aviation Administration." 14:14:3.0.1.4.33.9.3.1,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.251 Scope.,FAA,,,,This subpart sets forth minimum requirements for the approval and operation of non-Federal Interim Standard Microwave Landing System (ISMLS) facilities that are to be involved in the approval of instrument flight rules and air traffic control procedures related to those facilities. 14:14:3.0.1.4.33.9.3.10,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.269 Marker beacon performance requirements.,FAA,,,,ISMLS marker beacon equipment must meet the performance requirements prescribed in subpart H of this part. 14:14:3.0.1.4.33.9.3.11,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.271 Installation requirements.,FAA,,,"[Docket 14120, 40 FR 36110, Aug. 19, 1975, as amended by Amdt. 171-16, 56 FR 65665, Dec. 17, 1991]","(a) The ISMLS facility must be permanent in nature, located, constructed, and installed according to accepted good engineering practices, applicable electric and safety codes, FCC licensing requirements, and paragraphs (a) and (c) of § 171.261. (b) The ISMLS facility must have a reliable source of suitable primary power, either from a power distribution system or locally generated. Adequate power capacity must be provided for the operation of test and working equipment of the ISMLS. (c) The ISMLS facility must have a continuously engaged or floating battery power source for the ground station for continued normal operation if the primary power fails. A trickle charge must be supplied to recharge the batteries during the period of available primary power. Upon loss and subsequent restoration of power, the batteries must be restored to full charge within 24 hours. When primary power is applied, the state of the battery charge may not affect the operation of the ISMLS ground station. The battery must permit continuation of normal operation for at least two hours under the normal operating conditions. The equipment must meet all specification requirements with or without batteries installed. (d) There must be a means for determining, from the ground, the performance of the equipment including antennae, both initially and periodically. (e) The facility must have, or be supplemented by, ground-air or landline communications services. At facilities within or immediately adjacent to controlled airspace and that are intended for use as instrument approach aids for an airport, there must be ground-air communications or reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communication facility. Compliance with this paragraph need not be shown at airports where an adjacent Federal Aviation Administration facility can communicate with aircraft on the ground at the airport and during the entire proposed instrument approach procedure. In addition, at low traffic density airports within or immediately adjacent to controlled airspace, and where extensive delays are not a factor, the requirements of this paragraph may be reduced to reliable communications (at least a landline telephone) from the airport to the nearest Federal Aviation Administration air traffic control or communications facility, if an adjacent Federal Aviation Administration facility can communicate with aircraft during the proposed instrument approach procedure, at least down to the minimum en route altitude for the controlled area. (f) Except where no operationally harmful interference will result, at locations where two separate ISMLS facilities serve opposite ends of a single runway, an interlock must ensure that only the facility serving the approach direction in use can radiate." 14:14:3.0.1.4.33.9.3.12,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.273 Maintenance and operations requirements.,FAA,,,,"(a) The owner of the facility must establish an adequate maintenance system and provide qualified maintenance personnel to maintain the facility at the level attained at the time it was commissioned. Each person who maintains a facility must meet at least the Federal Communications Commission's licensing requirements and show that he has the special knowledge and skills needed to maintain the facility, including proficiency in maintenance procedures and the use of specialized test equipment. (b) In the event of out-of-tolerance conditions or malfunctions, as evidenced by receiving two successive pilot reports, the owner must close the facility be ceasing radiation, and issue a “Notice to Airman” (NOTAM) that the facility is out of service. (c) The owner must prepare, and obtain approval of, an operations and maintenance manual that sets forth mandatory procedures for operations, periodic maintenance, and emergency maintenance, including instructions on each of the following: (1) Physical security of the facility. (2) Maintenance and operations by authorized persons. (3) FCC licensing requirements for operations and maintenance personnel. (4) Posting of licenses and signs. (5) Relation between the facility and FAA air traffic control facilities, with a description of the boundaries of controlled airspace over or near the facility, instructions for relaying air traffic control instructions and information, if applicable, and instructions for the operation of an air traffic advisory service if the facility is located outside of controlled airspace. (6) Notice to the Administrator of any suspension of service. (7) Detailed and specific maintenance procedures and servicing guides stating the frequency of servicing. (8) Air-ground communications, if provided, expressly written or incorporating appropriate sections of FAA manuals by reference. (9) Keeping of station logs and other technical reports, and the submission of reports required by § 171.275. (10) Monitoring of the ISMLS facility. (11) Inspections by United States personnel. (12) Names, addresses, and telephone numbers of persons to be notified in an emergency. (13) Shutdowns for periodic maintenance and issue of “Notices to Airmen” for routine or emergency shutdowns. (14) Commissioning of the ISMLS facility. (15) An acceptable procedure for amending or revising the manual. (16) An explanation of the kinds of activities (such as construction or grading) in the vicinity of the ISMLS facility that may require shutdown or recertification of the ISMLS facility by FAA flight check. (17) Procedures for conducting a ground check of the localizer course alignment, width, and clearance, glide path elevation angle and course width, and marker beacon power, and modulation. (18) The following information concerning the ISMLS facility: (i) Facility component locations with respect to airport layout, instrument runways, and similar areas. (ii) The type, make, and model of the basic radio equipment that provides the service. (iii) The station power emission and frequencies of the ISMLS localizer, glide path, beacon markers, and associated compass locators, if any. (iv) The hours of operation. (v) Station identification call letters and method of station identification and the time spacing of the identification. (vi) A description of the critical parts that may not be changed, adjusted, or repaired without an FAA flight check to confirm published operations. (d) The owner or his maintenance representative must make a ground check of the ISMLS facility periodically in accordance with procedures approved by the FAA at the time of commissioning, and must report the results of the checks as provided in § 171.275. (e) Modifications to an ISMLS facility may be made only after approval by the FAA of the proposed modification submitted by the owner. (f) The owner or the owner's maintenance representative must participate in inspections made by the FAA. (g) Whenever it is required by the FAA, the owner must incorporate improvements in ISMLS maintenance. (h) The owner or his maintenance representative must provide a sufficient stock of spare parts, including solid state components, or modules to make possible the prompt replacement of components or modules that fail or deteriorate in service. (i) FAA approved test instruments must be used for maintenance of the ISMLS facility. (j) The mean corrective maintenance time of the ISMLS equipment may not exceed 0.5 hours, with a maximum corrective maintenance time of not greater than 1.5 hours. This measure applies to failures of the monitor, transmitter and associated antenna assemblies, limited to unscheduled outage and out-of-tolerance conditions. (k) The mean time between failures of the ISMLS equipment may not be less than 1,500 hours. This measure applies to unscheduled outages, out-of-tolerance conditions, and failures of the monitor, transmitter, and associated antenna assemblies. (l) Inspection consists of an examination of the ISMLS equipment to ensure that unsafe operating conditions do not exist. (m) Monitoring of the ISMLS radiated signal must ensure a high degree of integrity and minimize the requirements for ground and flight inspection. The monitor must be checked periodically during the in-service test evaluation period for calibration and stability. These tests and ground checks of glide slope, localizer, and marker beacon radiation characteristics must be conducted in accordance with the maintenance requirements of this section." 14:14:3.0.1.4.33.9.3.13,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.275 Reports.,FAA,,,,"The owner of the ISMLS facility or his maintenance representative must make the following reports at the indicated time to the appropriate FAA Regional Office where the facility is located. (a) Facility Equipment Performance and Adjustment Data ( FAA Form 198 ). The FAA Form 198 shall be filled out by the owner or his maintenance representative with the equipment adjustments and meter readings as of the time of facility commissioning. One copy must be kept in the permanent records of the facility and two copies must be sent to the appropriate FAA Regional Office. The owner or his maintenance representative must revise the FAA Form 198 data after any major repair, modernization, or retuning to reflect an accurate record of facility operation and adjustment. In the event the data are revised, the owner or his maintenance representative shall notify the appropriate FAA Regional Office of such revisions, and forward copies of the revisions to the appropriate FAA Regional Office. (b) Facility Maintenance Log ( FAA Form 6030 - 1 ). FAA Form 6030-1 is a permanent record of all the activities required to maintain the ISMLS facility. The entries must include all malfunctions met in maintaining the facility including information on the kind of work and adjustments made, equipment failures, causes (if determined) and corrective action taken. In addition, the entries must include completion of periodic maintenance required to maintain the facility. The owner or his maintenance representative must keep the original of each form at the facility and send a copy to the appropriate FAA Regional Office at the end of each month in which it is prepared. However, where an FAA approved remote monitoring system is installed which precludes the need for periodic maintenance visits to the facility, monthly reports from the remote monitoring system control point must be forwarded to the appropriate FAA Regional Office, and a hard copy retained at the control point. (c) Technical Performance Record ( FAA Form 418 ). FAA Form 418 contains a record of system parameters, recorded on each scheduled visit to the facility. The owner or his maintenance representative shall keep the original of each month's record at the facility and send a copy of the form to the appropriate FAA Regional Office." 14:14:3.0.1.4.33.9.3.2,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.253 Definitions.,FAA,,,,"As used in this subpart: Angular displacement sensitivity (Glide Slope) means the ratio of measured DDM to the corresponding angular displacement from the appropriate reference line. Collocated ground station means the type of ground station which transmits two or more guidance signals simultaneously from a common location. Course line means the locus of points nearest to the runway centerline in any horizontal plane at which the DDM is zero. Course sector (full) means a sector in a horizontal plane containing the course line and limited by the loci of points nearest to the course line at which the DDM is 0.155. Course sector (half) means the sector in a horizontal plane containing the course line and limited by the loci of points nearest to the course line at which DDM is 0.0775. DDM means difference in depth of modulation. The percentage modulation depth of the larger signal minus the percentage modulation depth of the smaller signal, divided by 100. Displacement sensitivity (Localizer) means the ratio of measured DDM to the corresponding lateral displacement from the appropriate reference line. Facility Performance Category I—ISMLS means an ISMLS which provides guidance information from the coverage limit of the ISMLS to the point at which the localizer course line intersects the ISMLS glide path at a height of 200 feet or less above the horizontal plane containing the threshold. Glide path means that locus of points in the vertical plane containing the runway center line at which the DDM is zero, which, of all such loci, is the closest to the horizontal plane. Glide path angle (θ) means the angle between a straight line which represents the mean of the ISMLS glide path and the horizontal. Glide path sector (full) means the sector in the vertical plane containing the ISMLS glide path and limited by the loci of points nearest to the glide path at which the DDM is 0.175. The ISMLS glide path sector is located in the vertical plane containing the runway centerline, and is divided by the radiated glide path in two parts called upper sector and lower sector, referring respectively to the sectors above and below the glide path. Glide path sector (half) means the sector in the vertical plane containing the ISMLS glide path and limited by the loci of points nearest to the glide path at which the DDM is 0.0875. ISMLS Point ‘A’ means an imaginary point on the glide path/localizer course measured along the runway centerline extended, in the approach direction, four nautical miles from the runway threshold. ISMLS Point ‘B’ means an imaginary point on the glide path/localizer course measured along the runway centerline extended, in the approach direction, 3500 feet from the runway threshold. ISMLS Point ‘C’ means a point through which the downward extended straight portion of the glide path (at the commissioned angle) passes at a height of 100 feet above the horizontal plane containing the runway threshold. Interim standard microwave landing system (ISMLS) means a ground station which transmits azimuth and elevation angle information which, when decoded and processed by the airborne unit, provides signal performance capable of supporting approach minima for V/STOL and CTOL operations and operates with the signal format and tolerances specified in §§ 171.259, 171.261, 171.263, 171.265, and 171.267. Integrity means that quality which relates to the trust which can be placed in the correctness of the information supplied by the facility. Mean corrective time means the average time required to correct an equipment failure over a given period, after a service man reaches the facility. Mean time between failures means the average time between equipment failure over a given period. Reference datum means a point at a specified height located vertically above the intersection of the runway centerline and the threshold and through which the downward extended straight portion of the ISMLS glide path passes. Split type ground station means the type of ground station in which the electronic components for the azimuth and elevation guidance are contained in separate housings or shelters at different locations, with the azimuth portion of the ground station located at the stop end of the runway, and the elevation guidance near the approach end of the runway." 14:14:3.0.1.4.33.9.3.3,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.255 Requests for IFR procedures.,FAA,,,,"(a) Each person who requests an IFR procedure based on an ISMLS facility that he owns must submit the following information with that request: (1) A description of the facility and evidence that the equipment meets the performance requirements of §§ 171.259, 171.261, 171.263, 171.265, 171.267, and 171.269, and is installed in accordance with § 171.271. (2) A proposed procedure for operating the facility. (3) A proposed maintenance organization and a maintenance manual that meets the requirements of § 171.273. (4) A statement of intent to meet the requirements of this subpart. (5) A showing that the ISMLS facility has an acceptable level of operational reliability, maintainability and acceptable standard of performance. Previous equivalent operational experience with a facility with identical design and operational characteristics will be considered in showing compliance with this paragraph. (b) After the FAA inspects and evaluates the ISMLS facility, it advises the owner of the results and of any required changes in the ISMLS facility or in the maintenance manual or maintenance organization. The owner must then correct the deficiencies, if any, and operate the ISMLS facility for an inservice evaluation by the FAA." 14:14:3.0.1.4.33.9.3.4,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.257 Minimum requirements for approval.,FAA,,,,"(a) The following are the minimum requirements that must be met before the FAA approves an IFR procedure for a non-Federal ISMLS facility: (1) The performance of the ISMLS facility, as determined by flight and ground inspection conducted by the FAA, must meet the requirements of §§ 171.259, 171.261, 171.263, 171.265, 171.267, and 171.269. (2) The installation of the equipment must meet the requirements of § 171.271. (3) The owner must agree to operate and maintain the ISMLS facility in accordance with § 171.273. (4) The owner must agree to furnish periodic reports as set forth in § 171.275 and agree to allow the FAA to inspect the facility and its operation whenever necessary. (5) The owner must assure the FAA that he will not withdraw the ISMLS facility from service without the permission of the FAA. (6) The owner must bear all costs of meeting the requirements of this section and of any flight or ground inspection made before the ISMLS facility is commissioned, except that the FAA may bear certain costs subject to budgetary limitations and policy established by the Administrator. (b) If the applicant for approval meets the requirements of paragraph (a) of this section, the FAA approves the ISMLS facility for use in an IFR procedure. The approval is withdrawn at any time that the ISMLS facility does not continue to meet those requirements. In addition, the ISMLS facility may be de-commissioned whenever the frequency channel is needed for higher priority common system service." 14:14:3.0.1.4.33.9.3.5,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.259 Performance requirements: General.,FAA,,,,"(a) The ISMLS consists of the following basic components: (1) C-Band (5000 MHz-5030 MHz) localizer equipment, associated monitor system, and remote indicator equipment; (2) C-Band (5220 MHz-5250 MHz) glide path equipment, associated monitor system, and remote indicator equipment; (3) VHF marker beacons (75 MHz), associated monitor systems, and remote indicator equipment. (4) An ISMLS airborne receiver or a VHF/UHF ILS receiver modified to be capable of receiving the ISMLS signals. This modification requires the addition of a C-Band antenna, a converter unit, a microwave/ILS mode control, and a VHF/UHF receiver modification kit. (b) The electronic ground equipments in paragraph (a)(1), (2), and (3) of this section, must be designed to operate on a nominal 120/240 volt, 60 Hz, 3-wire single phase AC power source. (c) ISMLS ground equipment must meet the following service conditions: (1) AC line parameters, DC voltage, elevation, and duty: 120 V nominal value, 102 V to 138 V (±1 V).* 208 V nominal value, 177 V to 239 V (±2 V).* 240 V nominal value, 204 V to 276 V (±0.2 V).* AC line frequency (60 Hz), 57 Hz to 63 Hz (±0.2 Hz).* DC voltage (48 V), 44 V to 52 V (±0.5 V).* * Note: Where discrete values of the above frequency or voltages are specified for testing purposes, the tolerances given in parentheses indicated by an asterisk apply to the test instruments used to measure these parameters. Elevation, 0 to 10,000 ft. above sea level. Duty, continuous, unattended. 120 V nominal value, 102 V to 138 V (±1 V).* 208 V nominal value, 177 V to 239 V (±2 V).* 240 V nominal value, 204 V to 276 V (±0.2 V).* AC line frequency (60 Hz), 57 Hz to 63 Hz (±0.2 Hz).* DC voltage (48 V), 44 V to 52 V (±0.5 V).* * Note: Where discrete values of the above frequency or voltages are specified for testing purposes, the tolerances given in parentheses indicated by an asterisk apply to the test instruments used to measure these parameters. Elevation, 0 to 10,000 ft. above sea level. Duty, continuous, unattended. (2) Ambient conditions for localizer and glide path equipment: Temperature, −10 °C to + 50 °C. Relative humidity, 5% to 90%. Temperature, −10 °C to + 50 °C. Relative humidity, 5% to 90%. (3) Ambient conditions for marker beacon facilities and all other equipment installed outdoors (for example, antennae, field detectors, and shelters): Temperature, −50 °C. to + 70 °C. Relative humidity, 5% to 100%. Temperature, −50 °C. to + 70 °C. Relative humidity, 5% to 100%. (4) All equipment installed outdoors must operate satisfactorily under the following conditions: Wind velocity, 0-100 MPH (not including gusts). Hail stones, 1/2 ″ diameter. Rain, provide coverage through a distance of 5 nautical miles with rain falling at a rate of 50 millimeters per hour, and with rain falling at the rate of 25 millimeters per hour for the additional design performance range of the system. Ice loading, encased in 1/2 ″ radial thickness of clear ice. Wind velocity, 0-100 MPH (not including gusts). Hail stones, 1/2 ″ diameter. Rain, provide coverage through a distance of 5 nautical miles with rain falling at a rate of 50 millimeters per hour, and with rain falling at the rate of 25 millimeters per hour for the additional design performance range of the system. Ice loading, encased in 1/2 ″ radial thickness of clear ice. (d) The ISMLS must perform in accordance with the following standards and practices for Facility Performance Category I operation: (1) The ISMLS must be constructed and adjusted so that, at a specified distance from the threshold, similar instrumental indications in the aircraft represent similar displacements from the course line or ISMLS glide path, as appropriate, regardless of the particular ground installation in use. (2) The localizer and glide path components listed in paragraphs (a)(1) and (a)(2) of this section which form part of an ISMLS, must comply at least with the standard performance requirements specified herein. The marker beacon components listed in paragraph (a)(3) of this section which form part of an ISMLS, must comply at least with the standard performance requirements specified in subpart H of this part. (3) The ISMLS must be so designed and maintained that the probability of operation is within the performance requirements specified in § 171.273(k). (e) The signal format and pairing of the runway localizer and glide path transmitter frequencies of an ISMLS must be in accordance with the frequency plan approved by the FAA, and must meet the following signal format requirements: (1) The localizer and glide slope stations must transmit angular guidance information on a C-band microwave carrier on narrow, scanned antenna beams that are encoded to produce a modulation in space which, after averaging over several beam scans, is equivalent to the modulation used for conventional ILS as specified in subpart C of this part, except that the frequency tolerance may not exceed ±0.0001 percent. (2) Guidance modulation must be impressed on the microwave carrier of the radiated signal in the form of a summation of 90 Hz and 150 Hz sinusoidal modulation corresponding to the pointing direction of the particular beam which radiates the signal. (3) Each of the effective beam positions must be illuminated in a particular sequence for a short time interval. The modulation impressed on each beam must be a sample of the combined 90 Hz and 150 Hz waveform appropriate for that particular beam direction and time slot, and must be accomplished by appropriately varying the length of time the carrier is radiated during each beam illumination interval. (4) For those cases where the scanning beam fills the coverage space in steps, the incremental step must not exceed 0.6 times the beam width where the beam is in the proportional guidance sector. In the clearance region, the step may not exceed 0.8 times the beam width. (5) At least one pulse duration modulation (pdm) sample pulse per beam width of scan must be provided. (6) The minimum pulse duration must be 40 microseconds. (7) The minimum beam scan cycle must be 600 Hz. (8) The minimum duty ratio detectable by a receiver located anywhere in the coverage areas defined by this specification may not be less than 0.1. Detected duty ratio means the ratio of the average energy per scan detected at a point in space to the average energy per scan transmitted in all directions through the transmitting antenna. (9) The localizer must produce a C-band unmodulated reference frequency signal of sufficient strength to allow satisfactory operation of an aircraft receiver within the specified localizer and glide path coverage sectors. Pairing of this reference frequency with the localizer and glide slope frequencies must be in accordance with a frequency plan approved by the FAA." 14:14:3.0.1.4.33.9.3.6,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.261 Localizer performance requirements.,FAA,,,,"This section prescribes the performance requirements for localizer equipment components of the ISMLS. (a) The localizer antenna system must: (1) Be located on the extension of the centerline of the runway at the stop end; (2) Be adjusted so that the course line be on a vertical plane containing the centerline of the runway served; (3) Have the minimum height necessary to comply with the coverage requirements prescribed in paragraph (j) of this section; (4) Be located at a distance from the stop end of the runway that is consistent with safe obstruction clearance practices; (5) Not obscure any light of the approach landing system; and (6) Be installed on frangible mounts or beyond the 1000′ light bar. (b) On runways where limited terrain prevents the localizer antennae from being positioned on the runway centerline extended, and the cost of the land fill or a tall tower antenna support is prohibitive, the localizer antenna array may be offset, including a collocated ground station, so that the course intercepts the centerline at a point determined by the amount of the angular offset and the glide path angle. If other than a runway centerline localizer is used, the criteria in subpart C of part 97 of this chapter is applicable. (c) At locations where two separate ISMLS facilities serve opposite ends of of a single runway, an interlock must ensure that only the facility serving the approach direction being used will radiate. (d) The radiation from the localizer antenna system must produce a composite field pattern which is pulse duration modulated, the time average equivalent to amplitude modulation by a 90 Hz and 150 Hz tone. The localizer station must transmit angular guidance information over a C-band microwave carrier on narrow, scanned antenna beams that are encoded to produce a modulation in space which, after averaging over several beam scans, is equivalent to the modulation used for conventional ILS as specified in subpart C of this part. The radiation field pattern must produce a course sector with one tone predominating on one side of the course and with the other tone predominating on the opposite side. When an observer faces the localizer from the approach end of the runway, the depth of modulation of the radio frequency carrier due to the 150 Hz tone must predominate on his right hand and that due to the 90 Hz tone must predominate on his left hand. (e) All horizontal angles employed in specifying the localizer field patterns must originate from the center of the localizer antenna system which provides the signals used in the front course sector. (f) The ISMLS course sector angle must be adjustable between 3 degrees and 9 degrees. The applicable course sector angle will be established and approved on an individual basis. (g) The ISMLS localizer must operate in the band 5000 MHz to 5030 MHz. The frequency tolerance may not exceed ±0.0001 percent. (h) The emission from the localizer must be vertically polarized. The horizontally polarized component of the radiation of the course line may not exceed that which corresponds to a DDM error of 0.016 when an aircraft is positioned on the course line and is in a roll attitude of 20 degrees from the horizontal. (i) The localizer must provide signals sufficient to allow satisfactory operation of a typical aircraft installation within the localizer and glide path coverage sectors. The localizer coverage sector must extend from the center of the localizer antenna system to distances of 18 nautical miles minimum within ±10 degrees from the front course line, and 10 nautical miles minimum between ±10 degrees and ±35 degrees from the front course line. The ISMLS localizer signals must be receivable at the distances specified up from a surface extending outward from the localizer antenna and within a sector in the elevation plane from 0.300 to 1.750 of the established glide path angle (θ). (j) Except as provided in paragraph (k) of this section, in all parts of the coverage volume specified in paragraph (i) of this section, the peak field strength may not be less than −87 dBW/m 2 , and must permit satisfactory operational usage of ISMLS localizer facilities. (k) The minimum peak field strength on the ISMLS glide path and within the localizer course sector from a distance of 10 nautical miles to a height of 100 feet (30 meters) above the horizontal plane containing the threshold, may not be less than + 87 dBW/m 2 . (l) Above 16 degrees, the ISMLS localizer signals must be reduced to as low a value as practicable. (m) Bends in the course line may not have amplitudes which exceed the following: (n) The amplitudes referred to in paragraph (m) of this section are the DDMs due to bends as realized on the mean course line, when correctly adjusted. (o) The radio frequency carrier must meet the following requirements: (1) The nominal depth of modulation of the radio frequency carrier due to each of the 90 Hz and 150 Hz tones must be 20 percent along the course line. (2) The depth of modulation of the radio frequency carrier due to each of the 90 Hz and 150 Hz tones must be between 18 and 22 percent. (3) The frequency tolerance of the 90 Hz and 150 Hz modulated tones must be within ±25 percent. (4) Total harmonic content of the 90 Hz tone may not exceed 10 percent. (5) Total harmonic content of the 150 Hz tone may not exceed 10 percent. However, a 300 Hz tone may be transmitted for identification purposes. (6) At every half cycle of the combined 90 Hz and 150 Hz wave form, the modulation tones must be phase-locked so that within the half course sector, the demodulated 90 Hz and 150 Hz wave forms pass through zero in the same direction within 20 degrees with phase relative to the 150 Hz component. However, the phase need not be measured within the half course sector. (p) The mean course line must be adjusted and maintained within ±.015DDM from the runway centerline at the ISMLS reference datum. (q) The nominal displacement sensitivity within the half course sector at the ISMLS reference datum, must be 0.00145 DDM/meter (0.00044DDM/foot). However, where the specified nominal displacement sensitivity cannot be met, the displacement sensitivity must be adjusted as near as possible to that value. (r) The lateral displacement sensitivity must be adjusted and maintained within 17 percent of the nominal value. Nominal sector width at the ISMLS reference datum is 210 meters (700 feet). (s) The increase of DDM must be substantially linear with respect to angular displacement from the front course line where DDM is zero, up to angle on either side of the front course line where the DDM is 0.180. From that angle to ±10 degrees, the DDM may not be less than 0.180. From ±10 degrees to ±35 degrees, the DDM may not be less than 0.155. (t) The localizer must provide for the simultaneous transmission of an identification signal which meets the following: (1) It must be specific to the runway and approach direction, on the same radio frequency carrier, as used for the localizer function. (2) Transmission of the identification signal may not interfere in any way with the basic localizer function. (3) The signal must be produced by pulse duration modulation of the radio frequency carrier resulting in a detected audio tone in the airborne VHF receiver of 1020 Hz ±50Hz. (4) The depth of modulation must be between the limits of 10 and 12 percent. (5) The emissions carrying the identification signal must be vertically polarized. (6) The identification signal must employ the International Morse Code and consist of three letters. It must be preceded by the International Morse Code signal of the letter “M” followed by a short pause where it is necessary to distinguish the ISMLS facility from other navigational facilities in the immediate area. At airports where both an ISMLS and an ILS are in operation, each facility must have a different identification call sign. (7) The signal must be transmitted at a speed corresponding to approximately seven words per minute, and must be repeated at approximately equal intervals, not less than six times per minute, during which time the localizer is available for operational use. When the localizer is not available for transmission, the identification signal must be suppressed." 14:14:3.0.1.4.33.9.3.7,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.263 Localizer automatic monitor system.,FAA,,,,"(a) The ISMLS localizer equipment must provide an automatic monitor system that transmits a warning to designated local and remote control points when any of the following occurs: (1) A shift of the mean course line of the localizer from the runway centerline equivalent to more than 0.015 DDM at the ISMLS reference datum. (2) For localizers in which the basic functions are provided by the use of a single-frequency system, a reduction of power output to less than 50 percent of normal or a loss of ground station identification transmissions. (3) Changes of displacement sensitivity to a value differing by more than 17 percent from nominal value for the localizer. (4) Failure of any part of the monitor itself. Such failure must automatically produce the same results as the malfunctioning of the element being monitored. (b) Within 10 seconds of the occurrence of any of the conditions prescribed in paragraph (a) of this section, including periods of zero radiation, localizer signal radiation must cease or the navigation and identification components must be removed." 14:14:3.0.1.4.33.9.3.8,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.265 Glide path performance requirements.,FAA,,,"[Docket 14120, 40 FR 36110, Aug. 19, 1975; 40 FR 41093, Sept. 5, 1975; 40 FR 43719, Sept. 23, 1975]","This section prescribes the performance requirements for glide path equipment components of the ISMLS. These requirements are based on the assumption that the aircraft is heading directly toward the facility. (a) The glide slope antenna system must be located near the approach end of the runway, and the equipment must be adjusted so that the vertical path line will be in a sloping horizontal plane containing the centerline of the runway being served, and satisfy the coverage requirements prescribed in paragraph (g) of this section. For the purpose of obstacle clearance, location of the glide slope antenna system must be in accordance with the criteria specified in subpart C of part 97 of this chapter. (b) The radiation from the glide path antenna system must produce a composite field pattern which is pulse duration modulated by a 90 Hz and a 150 Hz tone, which is the time average equivalent to amplitude modulation. The pattern must be arranged to provide a straight line descent path in the vertical plane containing the centerline of the runway, with the 150 Hz tone predominating below the path and the 90 Hz tone predominating above the path to at least an angle equal to 1.752θ. As used in this section theta (θ), denotes the nominal glide path angle. The glide path angle must be adjusted and maintained within 0.075θ. (c) The glide path equipment must be capable of producing a radiated glide path from 3 to 9 degrees with respect to the horizontal. However, ISMLS glide path angles in excess of 3 degrees may be used to satisfy instrument approach procedures or to overcome an obstruction clearance problem, only in accordance with the criteria specified in subpart C of part 97 of this chapter. (d) The downward extended straight portion of the ISMLS glide path must pass through the ISMLS reference datum at a height ensuring safe guidance over obstructions and safe and efficient use of the runway served. The height of the ISMLS reference datum must be in accordance with subpart C of part 97 of this chapter. (e) The glide path equipment must operate in the band 5220 MHz to 5250 MHz. The frequency tolerance may not exceed ±0.0001 percent. (f) The emission from the glide path equipment must be vertically polarized. (g) The glide path equipment must provide signals sufficient to allow satisfactory operation of a typical aircraft installation insectors of 8 degrees on each side of the centerline of the ISMLS glide path, to a distance of at least 10 nautical miles up to 1.75θ and down to 0.45θ above the horizontal or to such lower angle at which 0.22 DDM is realized. (h) To provide the coverage for glide path performance specified in paragraph (g) of this section, the minimum peak field strength within this coverage sector must be −82 dBW/m 2 . The peak field strength must be provided on the glide path down to a height of 30 meters (100 feet) above the horizontal plane containing the threshold. (i) Bends in the glide path may not have amplitudes which exceed the following: The amplitude referred to is the DDM due to bends as realized on the mean ISMLS glide path correctly adjusted. In regions of the approach where ISMLS glide path curvature is significant, bend amplitude is calculated from the mean curved path, and not the downward extended straight line. (j) Guidance modulation must be impressed on the microwave carrier of the radiated glide slope signal in the form of a unique summation of 90 Hz and 150 Hz sinusoidal modulation corresponding to the point direction of the particular beam which radiates the signal. Each of the effective beam positions must be illuminated in sequence for a short time interval. The scan rate must be synchronous with the 90 and 150 Hz tone base. The modulation impressed on each beam must be a sample of the combined 90 Hz and 150 Hz waveform appropriate for that particular beam direction and time slot. The actual modulation must be accomplished by appropriately varying the length of time the carrier is radiated during each beam illumination interval. (k) The nominal depth of modulation of the radio frequency carrier due to each of the 90 Hz and 150 Hz tones must be 40 percent along the ISMLS glide path. The depth of modulation may not deviate outside the limits of 37.5 percent to 42.5 percent. (l) The following tolerances apply to the frequencies of the modulating tones: (1) The modulating tones must be 90 Hz and 150 Hz within 2.5 percent. (2) The total harmonic content of the 90 Hz tone may not exceed 10 percent. (3) The total harmonic content of the 150 Hz tone may not exceed 10 percent. (m) At every half cycle of the combined 90 Hz and 150 Hz wave form, the modulation must be phase-locked so that, within the ISMLS half glide path sector, the demodulated 90 Hz and 150 Hz wave forms pass through zero in the same direction within 20 degrees of phase relative to the 150 Hz component. However, the phase need not be measured within the ISMLS half glide path sector. (n) The nominal angular displacement sensitivity must correspond to a DDM of 0.0875 at an angular displacement above and below the glide path of 0.12θ. The glide path angular displacement sensitivity must be adjusted and maintained within ±25 percent of the nominal value selected. The upper and lower sectors must be as symmetrical as practicable within the limits prescribed in this paragraph. (o) The DDM below the ISMLS glide path must increase smoothly for decreasing angle until a value of 0.22 DDM is reached. This value must be achieved at an angle not less than 0.30θ above the horizontal. However, if it is achieved at an angle above 0.45θ, the DDM value may not be less than 0.22 at least down to an angle of 0.45θ." 14:14:3.0.1.4.33.9.3.9,14,Aeronautics and Space,I,J,171,PART 171—NON-FEDERAL NAVIGATION FACILITIES,I,Subpart I—Interim Standard Microwave Landing System (ISMLS),,§ 171.267 Glide path automatic monitor system.,FAA,,,,"(a) The ISMLS glide path equipment must provide an automatic monitor system that transmits a warning to designated local and remote control points when any of the following occurs: (1) A shift of the mean ISMLS glide path angle equivalent to more than 0.075θ. (2) For glide paths in which the basic functions are provided by the use of a single frequency system, a reduction of power output to less than 50 percent. (3) A change of the angle between the glide path and the line below the glide path (150 Hz predominating), at which a DDM of 0.0875 is realized by more than ±0.0375θ. (4) Lowering of the line beneath the ISMLS glide path at which a DDM of 0.0875 is realized to less than 0.75θ from the horizontal. (5) Failure of any part of the monitor itself. Such failure must automatically produce the same results as the malfunctioning of the element being monitored. (b) At glide path facilities where the selected nominal angular displacement sensitivity corresponds to an angle below the ISMLS glide path, which is close to or at the maximum limits specified, an adjustment to the monitor operating limits may be made to protect against sector deviations below 0.75θ from the horizontal. (c) Within 10 seconds of the occurrence of any of the conditions prescribed in paragraph (a) of this section, including periods of zero radiation, glide path signal radiation must cease." 17:17:2.0.1.1.31.1.1.1,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.1 Scope of rules.,CFTC,,,"[55 FR 41068, Oct. 9, 1990, as amended at 70 FR 2352, Jan. 13, 2005; 78 FR 1145, Jan. 8, 2013]","(a) Matters included. Unless specifically excluded by subsection (b), this part governs review by the Commission, pursuant to sections 17(h), (i) and (o) of the Commodity Exchange Act (“Act”), as amended, of any disciplinary action, membership denial action, registration action or member responsibility action taken by the National Futures Association or any registered futures association. Unless specifically indicated, references in this part to the National Futures Association shall also include any other registered futures association. (b) Matters excluded. The Commission will not review under these rules the following decisions by the National Futures Association: (1) A decision in a disciplinary action if the party aggrieved by the decision knowingly failed to pursue the right to appeal an adverse decision to the Appeals Committee of the National Futures Association and there are no extraordinary circumstances that otherwise warrant Commission consideration of the aggrieved party's appeal; (2) A decision in an arbitration action brought pursuant to section 17(b)(10) of the Act or any rule of the National Futures Association; (3) Suspension of a member based solely on that member's failure to pay National Futures Association dues; (4) A decision to disqualify any member for service on the National Futures Association Board of Directors, Business Conduct Committees, Hearing Committee or arbitration panels pursuant to the standards for service adopted by the National Futures Association to implement Commission rule 1.63; (5) Suspension of a member or a person associated with a member based solely on that person's failure to pay an arbitration award or a settlement agreement resulting from an arbitration action brought pursuant to section 17(b)(10) of the Act or rules and regulations of the National Futures Association, or a settlement agreement resulting from a mediation proceeding sponsored by the National Futures Association, unless there are extraordinary circumstances that involve something more than the ministerial application of a predetermined sanction, or raise a colorable claim that the National Futures Assocaition has acted arbitrarily. (c) Appeals from excluded decisions. If the General Counsel, or any employee under the General Counsel's supervision as the General Counsel may designate, determines that a notice of appeal submitted to the Commission is from a decision that is excluded from review under this part, the notice of appeal may be stricken and ordered to be returned to the aggrieved party who submitted it. (d) Applicability of these part 171 rules. Unless otherwise ordered, these rules will apply in their entirety to all appeals and matters relating thereto filed on or after October 31, 1990. Any part 171 proceeding commenced prior to October 31, 1990 continues to be governed by the procedures established in former subpart F of part 3 of the Commission's regulations, if applicable, or by the procedures established for that proceeding by Commission order. Parties to any proceeding pending on October 31, 1990 may, within 30 days after October 31, 1990 by written stipulation executed by all parties, and filed with the Proceedings Clerk before the Commission's final decision is rendered, elect to have the matter governed by the provisions of these part 171 rules." 17:17:2.0.1.1.31.1.1.10,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.10 Motions.,CFTC,,,,"(a) In general. An application for a form of relief not otherwise specifically provided for in this part shall be made by a written motion, filed with the Proceedings Clerk. The motion shall state the relief sought, basis for the relief and the authority relied upon. (b) Answers to motions. Unless otherwise provided, a party may file a written response to a motion within five days after service of the motion. (c) Motions for procedural orders. Motions for procedural orders, including motions for extensions of time, may be acted on at any time, without awaiting a response thereto. Any party adversely affected by such action may request reconsideration, vacation or modification of the action. (d) Dilatory motions. Frivolous or repetitive motions dealing with the same subject matter shall not be permitted." 17:17:2.0.1.1.31.1.1.11,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.11 Sanctions.,CFTC,,,,"In the event a party fails to fulfill his obligations under these Rules, the Commission may impose appropriate sanctions including dismissal of the appeal or summary reversal of the decision under appeal. Sanctions may be imposed on the motion of a party or on the Commission's own motion." 17:17:2.0.1.1.31.1.1.12,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.12 Settlement.,CFTC,,,,"At any time before the Commission has reached a final determination in a proceeding, the parties may request dismissal of the appeal based on a settlement agreement. If, in its view, the settlement is consistent with the public interest, the Commission will dismiss the proceeding." 17:17:2.0.1.1.31.1.1.13,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.13 Practice before the Commission.,CFTC,,,,"(a) Practice —(1) By non-attorneys. An individual may appear pro se (on his own behalf); a general partner may represent the partnership; a bona fide officer of a corporation, trust or association may represent the corporation, trust or association. (2) By attorneys. An attorney-at-law who is admitted to practice before the highest court in any State or territory, or of the District of Columbia, who has not been suspended or disbarred from appearance and practice before the Commission in accordance with the provisions of part 14 of this chapter may represent parties as an attorney in proceedings before the Commission. (b) Debarment of counsel or representative during the course of a proceeding. Whenever, while a proceeding is pending before the Commission, the Commission finds that a person acting as counsel or representative for any party to the proceeding is guilty of contemptuous conduct, the Commission may order that such person be precluded from further acting as counsel or representative in a proceeding subject to these rules. The Commission may suspend the proceedings for a reasonable time for the purpose of enabling the party to obtain other counsel or representative. (c) Withdrawal from representation. Withdrawal from representation of a party will be only by leave of the Commission. Such leave to withdraw may be subject to conditions including submission of an affidavit averring that the party represented has actual knowledge of the withdrawal and providing the name and address of a successor counsel (or representative) or a statement that the represented party has determined to proceed pro se. If the party proceeds pro se, the statement shall include the address where the party can thereafter be served." 17:17:2.0.1.1.31.1.1.14,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.14 Waiver of rules.,CFTC,,,,"To prevent undue hardship on any party or for other good cause shown, the Commission may waive any rule in this part in a particular case and may order proceedings in accordance with its direction. Such an order shall be based upon a determination that no party will be prejudiced thereby and that the ends of justice will be served. Reasonable notice will be given to all parties of any action taken pursuant to this paragraph." 17:17:2.0.1.1.31.1.1.2,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.2 Definitions.,CFTC,,,"[55 FR 41068, Oct. 9, 1990, as amended at 89 FR 71821, Sept. 4, 2024]","For purposes of this part: (a) Commission decisional employee includes any member of the Commission staff who participates in, or may be reasonably expected to participate in, the decisionmaking process in any proceeding under this part. It does not include Commissioners or members of their personal staff. (b) Disciplinary action includes any proceeding brought by the National Futures Association to enforce its rules that may result in expulsion, suspension, censure, bar from association with a member, fine in excess of $100 or any comparable sanction being imposed on a member or a person associated with a member. (c) Ex parte communication shall include any communication, whether written or oral, which is both (1) not preceded by reasonable notice to all parties to a proceeding, and (2) not made on the public record. It shall not include requests made to the Office of the General Counsel's Litigation, Enforcement, and Adjudication Section or Office of Proceedings for status reports or for an interpretation of these rules. (d) Final Decision means the decision that terminates the proceeding before the National Futures Association on the action that is the subject of the notice of appeal filed with the Commission. (e) To mail means to place in the United States mail (or to deliver to an overnight delivery service of established reliability) a properly addressed and post-paid document. Unless otherwise provided, documents filed and served by mail must be sent by no less expeditious means than first class United States mail. (f) Member includes any person admitted to membership by the National Futures Association. (g) Member Responsibility Action includes any action in which, based on a finding by the National Futures Association that there is reason to believe that summary action is necessary to protect the commodity futures markets, customers or other members of the association, a member or person associated with a member may be summarily suspended from membership or association with a member, required to restrict operations or otherwise directed to take remedial action. (h) Membership denial action includes any proceeding brought by the National Futures Association to (1) determine whether an applicant should be admitted to membership or be permitted to be associated with a member, (2) determine whether an applicant should be admitted to membership or be permitted to be associated with a member on a conditional basis, or (3) determine whether to revoke or restrict the membership or association status of any person who is a member or is associated with a member. (i) Party includes any person who has been the subject of a disciplinary action, membership denial action, or registration action by the National Futures Association; the National Futures Association itself; any person granted permission to participate as a party pursuant to § 171.27 of these rules; and any Division of the Commission that files a Notice of Appearance pursuant to § 171.28 of these rules. (j) Person associated with a member includes any person permitted to register as an associate of a member by the National Futures Association. (k) Record of the proceeding shall include the order appealed from, the findings or report on which the order is based, the pleadings, evidence and proceedings before the National Futures Association decisonmaker and a copy of any rule of the National Futures Association that is material to the order. (l) Registration action includes any proceeding brought by the National Futures Association, pursuant to authority delegated by the Commission, to grant, condition, deny, suspend, restrict, or revoke the registration of any person. (m) Rule of the National Futures Association includes any article of incorporation, bylaw, rule, regulation, resolution or written interpretation of stated policy of the National Futures Association." 17:17:2.0.1.1.31.1.1.3,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.3 Business address; hours.,CFTC,,,"[55 FR 41068, Oct. 9, 1990, as amended at 60 FR 49336, Sept. 25, 1995; 89 FR 71821, Sept. 4, 2024]","The headquarters of the Commission is located at Three Lafayette Centre, 1155 21st Street, NW., Washington, DC 20581. It is open each day, except Saturdays, Sundays, and legal public holidays, from 8:15 a.m. until 4:45 p.m., eastern standard time or eastern daylight savings time, whichever is currently in effect in Washington, DC." 17:17:2.0.1.1.31.1.1.4,17,Commodity and Securities Exchanges,I,,171,"PART 171—RULES RELATING TO REVIEW OF NATIONAL FUTURES ASSOCIATION DECISIONS IN DISCIPLINARY, MEMBERSHIP DENIAL, REGISTRATION AND MEMBER RESPONSIBILITY ACTIONS",A,Subpart A—General Provisions,,§ 171.4 Computation of time.,CFTC,,,,"(a) In general. In computing any period of time prescribed by these rules or allowed by the Commission, the day of the act, event, or default from which the designated period of time begins to run is not to be included. The last day of the period so computed is to be included unless it is a Saturday, a Sunday, or a legal holiday. In the latter circumstances, the period runs until the end of the next day which is not a Saturday, a Sunday, or a legal holiday. Intermediate Saturdays, Sundays, and legal holidays shall be included in the computation unless the period of time prescribed or allowed is less than seven (7) days. (b) Date of service of orders. In computing any period of time involving the date of service of an order, the date of service shall be the date the order is mailed or hand delivered by the Proceedings Clerk, which, unless otherwise indicated, shall be the date stamped on the order by the Proceedings Clerk."