Airworthiness Directives; Airbus Helicopters

DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2025-0910; Project Identifier MCAI-2023-01167-R]</DEPDOC> <RIN>RIN 2120-AA64</RIN> <SUBJECT>Airworthiness Directives; Airbus Helicopters</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Notice of proposed rulemaking (NPRM). <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA proposes to supersede Airworthiness Directive (AD) 2020-06-13, which applies to certain Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1 helicopters. AD 2020-06-13 requires determining the accumulated hours time-in-service (TIS) of certain part-numbered main gearbox (MGB) suspension bar rear attachment fittings (fittings) and bolts and establishes reduced life limits. Since the FAA issued AD 2020-06-13, it was determined that modifying the MGB suspension bar fittings link and installing improved MGB suspension bar fitting bolts are necessary. This proposed AD would require modifying the MGB suspension bar link, installing newly-designed bolts, and prohibit installing certain parts. The FAA is proposing this AD to address the unsafe condition on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> The FAA must receive comments on this NPRM by July 7, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • <E T="03">Federal eRulemaking Portal:</E> Go to <E T="03">regulations.gov.</E> Follow the instructions for submitting comments. • <E T="03">Fax:</E> (202) 493-2251. • <E T="03">Mail:</E> U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. • <E T="03">Hand Delivery:</E> Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. <E T="03">AD Docket:</E> You may examine the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2025-0910; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. <E T="03">Material Incorporated by Reference:</E> • For EASA material identified in this proposed AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: <E T="03">ADs@easa.europa.eu;</E> website: <E T="03">easa.europa.eu.</E> You may find this material on the EASA website at <E T="03">ad.easa.europa.eu.</E> • You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222-5110. It is also available at <E T="03">regulations.gov</E> under Docket No. FAA-2025-0910. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Camille Seay, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817) 222-5149; email: <E T="03">camille.l.seay@faa.gov</E> . </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Comments Invited</HD> The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the <E T="02">ADDRESSES</E> section. Include “Docket No. FAA-2025-0910; Project Identifier MCAI-2023-01167-R” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend the proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to <E T="03">regulations.gov,</E> including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. <HD SOURCE="HD1">Confidential Business Information</HD> CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Camille Seay, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. <HD SOURCE="HD1">Background</HD> The FAA issued AD 2020-06-13, Amendment 39-19882 (85 FR 19080, April 6, 2020) (AD 2020-06-13), for Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1 helicopters with an MGB suspension bar right-hand (RH) side rear fitting part number (P/N) 330A22-2702-07 and bolt P/N 330A22-0135-20, MGB suspension bar left-hand (LH) side rear fitting P/N 330A22-2702-06 and bolt P/N 330A22-0135-20, or MGB suspension bar front bolt P/N 330A22-0134-20 installed. AD 2020-06-13 was prompted by an MCAI originated by EASA, which is the Technical Agent for the Member States of the European Union. EASA issued AD 2018-0260, dated December 3, 2018 (EASA AD 2018-0260), to address MGB suspension bar fittings and bolts remaining in service beyond their fatigue life. From review of reported Model EC 225 LP data, EASA advised that the installation of the MGB upper deck fittings of the three MGB suspension bars (front, RH side rear, and LH side rear) could lead to tightening torque loss on the fittings' attachment screws (bolts). Due to design similarities, Model AS 332 C, AS 332 C1, AS 332 L, and AS 332 L1 helicopters could also be affected by the same installation condition. AD 2020-06-13 requires determining the total hours TIS of the MGB suspension bar RH side and LH side rear fittings, removing these fittings and bolts from service based on the accumulated total hours TIS and other conditions, and thereafter removing these fittings and bolts from service within specific intervals. AD 2020-06-13 also requires removing the front bolts from service during each major inspection “G.” The FAA issued AD 2020-06-13 to prevent failure of an MGB attachment assembly, detachment of an MGB suspension bar, and consequent loss of helicopter control. <HD SOURCE="HD1">Actions Since AD 2020-06-13 Was Issued</HD> Since the FAA issued AD 2020-06-13, EASA superseded EASA AD 2018-0260 and issued EASA AD 2023-0194, dated November 8, 2023 (EASA AD 2023-0194), to address an unsafe condition on all Airbus Helicopters Model AS 332 C, AS 332 C1, AS 332 L, and AS 332 L1 helicopters. EASA AD 2023-0194 stated that, following the loss of tightening torque of the attachment screws of the upper deck fittings of the three MGB suspension bars and previous interim action, Airbus Helicopters developed modification (mod) 0728496 (for helicopters with machined frames) and mod 0729200 (for helicopters with sheet metal frames), which improve the link of the fittings of the MGB suspension bars and include improved fitting screws. After EASA issued EASA AD 2023-0194, EASA superseded EASA AD 2023-0194 with EASA AD 2023-0194R1 Revision 1, dated March 19, 2025 (EASA AD 2023-0194R1) (also referred to as the MCAI). The MCAI states that since EASA AD 2023-0194 was issued, a new risk analysis determined the calendar time compliance time for the modification can be extended. The MCAI further states that EASA AD 2023-0194R1 is considered to be an interim action. This condition, if not addressed, could lead to structural failure of an MGB attachment assembly, detachment of an MGB suspension bar, and consequent loss of control of the helicopter. The FAA is proposing this AD to address the unsafe condition on these products. You may examine the MCAI in the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2025-0910. <HD SOURCE="HD1">Material Incorporated by Reference Under 1 CFR Part 51</HD> The FAA reviewed EASA AD 2023-0194R1, which specifies procedures for determining the accumulated service life of the RH side and LH side rear fittings of the MGB suspension bars and repetitively replacing the RH side and LH side rear fittings and screws before exceeding accumulated service life limits. As an alternative to the first replacement of the RH side rear fittings and screws, if certain conditions are met, EASA AD 2023-0194R1 allows measuring the tightening torque, and depending on the measurement results, replacing affected parts with serviceable parts within extended compliance times. EASA AD 2023-0194R1 also specifies procedures for replacing each MGB front fitting screw at the next major inspection (G) and modifying the helicopter to improve the link of the fittings of the MGB suspension bar, which includes installing MGB fitting screws with an improved design. EASA AD 2023-0194R1 prohibits installing certain parts on any helicopter. Finally, EASA AD 2023-0194R1 specifies procedure ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 25k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━