Legal Interpretations
Fields - 2024 Legal Interpretation 14 CFR §§ 145.59 and 145.61 for Repair Systems
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Federal Aviation Administration Memorandum
Date: July 17, 2023
To: Lawrence Fields, Acting Executive Director, Flight Standards Service, AFX-1
From: Laura Megan-Posch, Assistant Chief Counsel for Regulations, AGC-200
Prepared by: Richard Doan, Senior Attorney, AGC-210
Subject: Re: Request for Legal Interpretation of Title 14 Code of Federal Regulations (14 CFR) Sections 145.59 and 145.61 for Repair Stations This memorandum is in response to a July 20, 2017, request from John S. Duncan (then AFX-1) for a legal interpretation of 14 Code of Federal Regulations (14 CFR) part 145 pertaining to ratings issued to certificated repair stations. Specifically, you seek guidance in resolving an apparent regulatory conflict that arises when a repair station is issued a class rating under § 145.59 and a limited rating under § 145.61 for the same article. You then pose a series of questions that address this and other related concerns under part 145.
During a regional audit of part 145 Operations Specifications (OpSpecs) paragraphs, the Central Region Technical Branch – General Aviation, ACE-230, identified a recurring issue regarding the issuance of limited ratings for articles that are already covered by an existing class rating. You are concerned that this duplicative condition creates a conflicting situation between the limitations imposed on a limited rating and the more general class rating. For example, you raise a scenario where a repair station with an airframe class rating has also been issued a limited rating for a specific airframe that prohibits major structural repairs on that airframe. You ask whether the repair station is still authorized under the class rating to perform the major structural repair even though the limitations in the limited rating prohibit the repair. The Federal Aviation Administration’s (FAA) rules provide for two categories of repair station ratings that define and govern which articles repair stations may work on under the part 145 regulations. These are class ratings and limited ratings. Section 145.59 identifies the class ratings that can be issued to a certificated repair station. Class ratings are broadly defined and generally cover all articles, including aircraft types, listed in the category.1 1 We are aware that class ratings sometimes are issued with limitations on the types of aircraft for which the repair station can provide maintenance. As this memorandum discusses, however, the issuance of limited ratings instead of class ratings with limitations is, in general, the more appropriate method when the repair station is unable to service all articles, including aircraft, within the class rating. See FAA Order 8900.1, Vol. 2, Ch. 11, Sec. 6, Para. 2- 1260 (“NOTE: … A class rating does not have restrictions for a specific product. If any restrictions or limitations apply, then a limited rating would be issued in lieu of the class rating”). Nonetheless, the regulations do not LAURA JANE MEGANPOSCH Digitally signed by LAURA JANE MEGAN-POSCH
Date:
2023.07.17 10:56:23 -04'00'
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Pursuant to § 145.61, however, the FAA may issue limited ratings to a repair station that “maintains or alters only a particular type of airframe, powerplant, propeller, radio, instrument, or accessory, or part thereof, or performs only specialized maintenance requiring equipment and skills not ordinarily performed under other repair station ratings.” Section 145.61(b) identifies 12 categories of aircraft articles and a thirteenth “catch-all” category for which the FAA may issue limited ratings.
A § 145.61 limited rating should not be issued for an article that is already covered by a repair station’s broader § 145.59 class rating. These two provisions are designed to be mutually exclusive with respect to articles that fall within the same categories. When the FAA’s predecessor agency (the Civil Aeronautics Board) first promulgated the rule allowing for limited ratings, it described the class ratings in § 145.59 (then § 52.26) as “general ratings” covering airframe, powerplant, propeller, radio, instrument, and accessory. The Board then explained that the limited ratings provided for in § 145.61 (then § 52.27) may be issued instead of the general class ratings. For example, an applicant for a powerplant rating would not have to be equipped to repair all powerplants, but, with a limited rating, may choose the make or model with which he desires to work. See 17 FR 2981 (Apr. 5, 1952). Limited ratings are not intended to be issued in addition to the broader class rating. This basic regulatory framework has not changed in the intervening years, and we are not aware of any policy reasons for interpreting the current, recodified regulations any differently.
Accordingly, a limited rating should not be issued under § 145.61 if it will duplicate and conflict with a class rating issued under § 145.59. Having established this general principle, we now turn to the related questions you pose.
Question 1: If a part 145 certificated repair station holds an Airframe Class 3 rating, all-metal construction of small aircraft, does this rating authorize the repair station to conduct maintenance on all type certificated, small fixed wing single/multi-engine airplane and rotorcraft?
Response: Generally, yes, so long as they are of all-metal construction. Section 145.201(a)(1) provides that a certificated repair station may perform maintenance, preventive maintenance, or alterations in accordance with 14 CFR part 43 on any article for which it is rated and within the limitations in its operations specifications. Thus, a repair station with an Airframe Class 3 rating under § 145.59 would be authorized, consistent with its operating specifications and subject to the operating rules in subpart E, to conduct maintenance on the all-metal constructed “airframe” of “small aircraft,” which, as these terms are defined in 14 CFR § 1.1, would include all type certificated, small fixed wing single and multi-engine “airplane” and small “rotorcraft.” Question 2: To be issued an Airframe Class 4 rating, all-metal construction of large aircraft (e.g., Boeing 747, McDonnel Douglas MD-11, Learjet 35, Bombardier Challenger 604, and large rotorcraft such as Airbus H215 or Sikorsky S-64 Skycrane), expressly prohibit the use of limitations with class ratings. Therefore, in certain circumstances (e.g., where the repair station is unable to service only a few, less common articles within the class category), it may be more practicable to issue a class rating with limitations specifying the types of aircraft that may not be serviced.
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§ 145.51 states that the equipment, personnel, technical data, and housing and facilities required for certification and rating, or for an additional rating, must be in place for inspection at the time of certification or rating approval.
a. Is the repair station obligated to meet the requirements for the entire range of aircraft types encompassed by the Airframe Class 4 rating?
Response: Generally, yes, a repair station with an Airframe Class 4 rating under § 145.59 would be obligated to meet the requirements for the entire range of aircraft types encompassed by the class rating, as specified in its operations specification.2 Subpart C of part 145 sets forth the requirements for housing, facilities, equipment, materials, and data, while subpart D prescribes requirements for personnel. In order to be approved for a repair station certificate, § 145.51(b) requires that the equipment, personnel, technical data, and housing and facilities needed for a particular rating must be in place for inspection at the time of rating approval by the FAA. Note, however, that the rule also provides that “the requirement to have the equipment in place at the time of initial certification or rating approval may be met if the applicant has a contract acceptable to the FAA with another person to make the equipment available to the repair station at any time it is necessary when the relevant work is being performed.” Note, also, that § 145.109(a) provides that the “equipment, tools, and material must be located on the premises and under the repair station’s control when the work is being done.”
b. Does the repair station need to demonstrate the housing capability for all large metal aircraft in the above example to meet the requirements of § 145.103(a)(1)?
Response: Generally, yes. As stated in the preceding response, a repair station with an Airframe Class 4 rating under § 145.59 would be obligated to meet the requirements for the entire range of aircraft types encompassed by the class rating, as specified in its operations specification.3 Section 145.101 requires that a certificated repair station provide housing that meets the applicable requirements for the issuance of the certificate and ratings the repair station holds. Section 145.103(a)(1) requires that each certificated repair station provide housing for the facilities, equipment, materials, and personnel consistent with its ratings and limitations. Accordingly, a repair station with a class rating issued under § 145.59 (and no further limitations in its operations specifications for that class rating), would be obligated to provide suitable housing for the entire range of aircraft types encompassed by that class rating. In contrast, a repair station with a limited class rating under § 145.61 need only provide suitable housing to meet the range of aircraft types specified in the limitations in its operations specifications.4 Question 3: Section 145.59 does not define eligibility to hold a class rating. FAA Order 8900.1, Vol. 2, Ch. 11, Sec. 6 provides guidance criteria for issuance of a class rating and Paragraph 2-1260 contains a note stating: “Class ratings are issued if the repair station can prove its capability to maintain a representative number of makes and models. A 2 But see supra note 1.
3 But see supra note 1.
4 For additional information on this distinction, see the preamble to the 2016 interim final rule revising §§ 145.61 and 145.103, 81 FR 49158 (Jul. 27, 2016).
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class rating does not have restrictions for a specific product. If any restrictions or limitations apply, then a limited rating would be issued in lieu of the class rating.” a. Is there a legal definition of what would constitute a representative number of makes and models?
Response: Section 145.53 states, in pertinent part, that a person who meets the requirements of subparts A through E of part 145 is entitled, with certain exceptions, to a repair station certificate with “appropriate” ratings. FAA regulations do not further define or elaborate on the criteria to determine what ratings are appropriate. This evaluation should be accomplished by the FAA on a case-by-case basis, depending on the unique circumstances of each applicant for repair station certification. As discussed above, the class ratings set forth in § 145.59 are broadly defined and generally cover all articles listed in the category. Therefore, the guidance provided in FAA Order 8900.1, Vol. 2, Ch. 11, Sec. 6, Para. 2-1260 is appropriate because a repair station’s capability to maintain a “representative number of makes and models” helps demonstrate that it can perform the broad work for which it will be rated. The exact number of makes and models of aircraft that should be considered in order for it to be representative, or typical, of the applicable class rating category is a policy determination for the relevant FAA program office to make.
b. Could a representative number of makes and models under an Airframe Class rating be comprised of only fixed wing aircraft?
Response: As explained in the preceding response, the relevant FAA program office should determine, based on each applicant repair station’s circumstances, the criteria to use in determining the appropriate ratings to be issued.
c. If the repair station was not capable of or did not meet the requirements for rotorcraft, could it still be issued the Airframe Class rating? Response: Separate class ratings do not exist for rotorcraft. A repair station that cannot meet the requirements in part 145 for the repair of both small and large rotorcraft airframes should not be issued an Airframe Class rating, which is broadly defined and covers the repair of airframes for small and large aircraft. The repair station should instead be issued limited ratings with appropriate limitations excluding work on rotorcraft airframe.
Please note, however, that § 145.59(a) distinguishes between small aircraft (Airframe Class 1 and Class 3), which includes small rotorcraft, and large aircraft (Airframe Class 2 and Class 4), which includes large rotorcraft. Thus, a repair station that cannot meet the requirements for the repair of large rotorcraft airframes but is still able to meet the requirements for the repair of small rotorcraft airframes, may be issued an Airframe Class 1 or 3 rating, as applicable. Question 4: With the exception of repairs or alterations to powerplants, propellers, instruments, or radios, does an Airframe Class 4 rating authorize all other maintenance on the aircraft? (Example: Landing gear systems and components, fuel systems and components, hydraulic systems and components, non-destructive inspection, machining, and welding).
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Response: An Airframe Class 4 rating authorizes maintenance on the “airframe” of all-metal construction of large aircraft, of which a major portion of the airframe is all metal construction. See FAA Order 8900.1, Vol. 2, Ch. 11, Sec. 6, Para. 2-1260. Included within the definition of “airframe” are the “fuselage, booms, nacelles, cowlings, fairings, airfoil surfaces (including rotors but excluding propellers and rotating airfoils of engines), and landing gear of an aircraft and their accessories and controls.” See § 1.1. As you mention, the airframe does not include powerplants, propellers, instruments, or radios, among other things, but it does include parts, accessories, and controls appurtenant to the items listed in the definition of “airframe.” Thus, turning to your examples, an Airframe class rating would authorize maintenance, including any associated machining and welding, on the landing gear systems and components and the hydraulic systems and components that are appurtenant to the airframe. It would also authorize non-destructive inspection of the airframe. While some aspects of the fuel system and components are considered part of the airframe, other fuel system parts and components are considered part of the powerplant. Those non-airframe parts and components of the fuel system would not be included in the Airframe Class 4 rating. A powerplant class rating under § 145.59(b) (or a limited rating under § 145.61) would be needed. Question 5: Does an Airframe Class rating or Limited Airframe rating authorize only maintenance and approval for return to service of the airframe? Response: As discussed in the previous response, an Airframe Class rating authorizes maintenance only on the “airframe,” as defined in § 1.1. In general, the same authorization applies to a Limited Airframe rating under § 145.61, subject to the limitations in the repair station’s operations specifications. See FAA Order 8900.1, Vol. 2, Ch. 11, Sec. 6, Para. 2- 1261.E., for additional examples of what may also be worked on under a limited airframe rating. a. Could a component be removed from the airframe, repaired, and given a maintenance release on a FAA Form 8130-3 under either Airframe rating to meet 14 CFR § 43.9 requirements?
Response: Yes, assuming all regulatory requirements are met, a repair station with either an airframe class rating or a limited airframe rating can remove and repair an airframe component and release it for return to service on FAA Form 8130-3 (Authorized Release Certificate, also referred to as an Airworthiness Approval Tag) to meet § 43.9 requirements. Question 6: Can a part 145 certificated repair station be issued OpSpecs that authorize an Airframe Class 4 rating and a Limited Airframe rating, where both ratings authorize the repair station to perform the same maintenance on the same airframe without being contrary to § 145.61(a)? (Example: An Airframe Class 4 rating and a Limited Airframe rating for a Boeing 747 aircraft).
a. If the Limited Airframe rating included a limitation in OpSpecs which excludes major structural repairs, could the repair station still perform major structural repairs on a B-747 utilizing the Airframe Class 4 rating?
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b. Would one of the Airframe ratings (Class or Limited) take precedence over the other?
c. In this example, does the repair station meet the requirements to hold an Airframe Class 4 rating if it does not have the capability to perform major structural repairs on a B-747?
Response: As explained in more detail above, a limited rating should not be issued under § 145.61 if it will duplicate and conflict with a class rating issued under § 145.59. Where a repair station has been issued both ratings, we recommend that one of the ratings, as appropriate, be removed through an amendment of the certificate.
Question 7: Can §§ 145.51, 145.53, 145.59 and 145.61 for the issuance of a repair station certificate also be used by the FAA to make certificate and OpSpecs amendments when:
a. The FAA determines that a repair station no longer meets the criteria of subparts A through E of part 145 to hold a class rating?
b. The FAA discovers errors in the issuance or qualifications of the repair station after the repair station is certificated and ratings issued? Response: When the FAA determines that a repair station no longer meets the criteria to hold a class rating or discovers errors in the issuance or qualifications of a certificated repair station, the FAA has discretion to take certificate action to amend, modify, suspend, or revoke the part 145 certificate, in accordance with the provisions of 49 U.S.C. § 44709(b), 14 CFR part 13, and agency policies. Therefore, in order to avoid FAA certificate action or other penalty, the repair station should be advised to amend its certificate or rating in such a way that it can still comply with all regulatory requirements. Section 145.57 sets forth the procedures for when a certificate holder applies for an amendment to its certificate. Moreover, for repair stations located outside of the United States, §§ 145.55(b) and (c) require certificate renewal, and the FAA may deny renewal if the foreign-located repair station no longer meets all regulatory requirements. Question 8: Section 145.57(a) allows a repair station to apply for changes to its certificate by formal request acceptable to the FAA. Would the repair station need to voluntarily request the FAA remove a rating or does this require an enforcement action to remove the rating should the repair station not agree to voluntarily surrender the rating at the request of the FAA?
Response: Section 145.57(a) generally applies only where the certificated repair station voluntarily applies to amend its certificate or rating. The regulation does, however, make it a requirement for a repair station to amend its certificate if it (1) changes the name or location of the repair station; or (2) requests to add or amend a rating.
If the FAA determines that a repair station is no longer qualified to hold a certain rating and the repair station does not agree to voluntarily surrender the rating, an enforcement action may be
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necessary to amend, modify, suspend, or revoke the certificate or rating. See 49 U.S.C. § 44709(b).
Question 9: Section 145.53 states that a person who meets the requirements of subparts A through E of part 145 is entitled to a repair station certificate with appropriate ratings. a. Does § 145.53(a) entitle a repair station to receive a Limited rating for an article if the repair station is currently appropriately rated to maintain that same article under a Class rating?
b. Could the FAA deny a repair station application to add a Limited rating for an article on the basis that an entitled appropriate Class rating is already authorized under § 145.59?
Response: Under § 145.53(a), the applicant is entitled to a repair station certificate with “appropriate” ratings. As explained in more detail above, a limited rating issued under § 145.61 is not appropriate if it will duplicate and conflict with a class rating issued under § 145.59. Accordingly, if a repair station is seeking a limited rating for an article that is already covered by its class rating, the FAA should deny the application unless the repair station agrees to surrender its class rating.
Question 10: If a repair station requesting a duplicative certification with Class and Limited ratings for the same products/articles and denied that request even though it submits examples of other repair stations having the same ratings, does this place the FAA in a position of granting favoritism or providing a financial advantage of one repair station over another?
Response: As explained above, a limited rating should not be issued under § 145.61 if it will duplicate and conflict with a class rating issued under § 145.59. Where such duplicative ratings have been issued to repair stations in the past, we recommend that these repair stations be asked to surrender either the limited rating or the class rating, as appropriate.
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