Airworthiness Directives; Airbus Helicopters

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2024-2419; Project Identifier MCAI-2023-00366-R; Amendment 39-22992; AD 2025-06-04]</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> Final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters (Airbus) Model AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350D, AS355E, AS355F, AS355F1, AS355F2, AS355N, AS355NP, EC130B4, and EC130T2 helicopters. This AD was prompted by a manufacturer assessment that determined additional actions are necessary to improve particle detection for main gearboxes (MGBs) with certain planet gear bearings installed. This AD requires repetitively inspecting the MGB bevel wheel and the MGB magnetic plug for particles and prohibits installing an affected MGB unless certain requirements are met. These actions are specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This AD is effective May 9, 2025. The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 9, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> <E T="03">AD Docket:</E> You may examine the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2024-2419; 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 final rule, the EASA AD, any comments received, and other information. The address for Docket Operations is 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">Material Incorporated by Reference:</E> • For EASA material identified in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: <E T="03">ADs@easa.europa.eu.</E> You may find the EASA 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-2024-2419. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Dan McCully, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (404) 474-5548; email: <E T="03">william.mccully@faa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Background</HD> The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Airbus Model AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350D, AS355E, AS355F, AS355F1, AS355F2, AS355N, AS355NP, EC130B4, and EC130T2 helicopters. The NPRM published in the <E T="04">Federal Register</E> on November 5, 2024 (89 FR 87821). The NPRM was prompted by EASA AD 2023-0044, dated February 28, 2023, (EASA AD 2023-0044), issued by EASA, which is the Technical Agent for the Member States of the European Union. EASA advises that after a fleet design review for detection of particles in the MGB, it was determined that additional maintenance actions are necessary to improve detection of particles in the MGB. In the NPRM, the FAA proposed to require repetitively inspecting the MGB bevel wheel for the presence of particles, repetitively inspecting the MGB magnetic plug for particles, close monitoring of the MGB magnetic plug if it has particles, and replacing the epicyclic module if necessary. The NPRM also proposed to prohibit installing an affected MGB unless certain requirements are met. The FAA is issuing this AD to detect and correct the presence of particles in the MGB, which if not addressed, could result in reduced or loss of control of the helicopter. You may examine EASA AD 2023-0044 in the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2024-2419. <HD SOURCE="HD1">Discussion of Final Airworthiness Directive</HD> <HD SOURCE="HD1">Comments</HD> The FAA received no comments on the NPRM or on the determination of the costs. <HD SOURCE="HD1">Conclusion</HD> These products have been approved by the aviation authority of another country and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the EASA AD referenced above. The FAA reviewed the relevant data and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator. <HD SOURCE="HD1">Material Incorporated by Reference Under 1 CFR Part 51</HD> EASA AD 2023-0044 requires repetitive borescope visual inspections of the bevel wheel of the affected MGB for particles, collecting and analyzing any found particles, and depending on the results, further actions, accomplishing corrective action in accordance with the ASB defined within, or contacting AH [Airbus Helicopters] for further corrective action. EASA AD 2023-0044 also requires accomplishing a borescope visual inspection of the bevel wheel of the affected MGB for particles following the detection of any particles at the MGB magnetic plug during accomplishment of certain maintenance tasks and depending on the results, taking corrective action. Lastly, EASA AD 2023-0044 prohibits installing an affected MGB on any helicopter unless it is a serviceable part as defined within and certain requirements are met. This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the <E T="02">ADDRESSES</E> section. <HD SOURCE="HD1">Differences Between this AD and EASA AD 2023-0044</HD> EASA AD 2023-0044 applies to Model AS350BB helicopters, whereas this AD does not because that model is not FAA-type certificated. Where Note 1 in the material referenced in EASA AD 2023-0044 specifies the option of 1 mechanical technician and 1 crew member, for this AD, the pilot is only permitted to turn the tail rotor (b) because the other actions specified in the note must be accomplished by persons authorized under 14 CFR 43.3. Therefore, for the purpose of this AD, the owner/operator (pilot) may turn the tail rotor (b) and must enter compliance with the applicable paragraph of this AD in the helicopter maintenance records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The pilot may perform this action because it only involves turning the tail rotor (b). This action can be performed equally well by a pilot or a mechanic. This action is an exception to the FAA's standard maintenance regulations. This AD does not require complying with paragraph (2) of EASA AD 2023-0044. Instead, this AD requires repetitively inspecting the MGB magnetic plug for particles and, if there is any particle, accomplishing a borescope visual inspection, as specified in paragraphs (h)(6)(i) and (ii) of this AD. Where the material referenced in EASA AD 2023-0044 specifies contacting Airbus Helicopters for a certain action, this AD requires accomplishing action in accordance with a method approved the FAA, EASA, or Airbus Helicopters' EASA Design Organization Approval. <HD SOURCE="HD1">Costs of Compliance</HD> The FAA estimates that this AD affects 522 helicopters of U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the following costs to comply with this AD. A repetitive visual borescope inspection of the MGB bevel wheel will take 1 work-hour for an estimated cost of $85 per helicopter and $44,370 for the U.S. fleet, per inspection cycle. If necessary, collecting and performing a metallurgical analysis of the detected particles will take 6 work-hours for an estimated cost of $510 per helicopter, per analysis. Repetitively inspecting the magnetic plugs of the MGB will take 1 work-hour for an estimated cost of $85 per helicopter and $44,370 for the U.S. fleet, per inspection cycle. If required, close monitoring will take 2 work-hours for an estimated cost of $170 per helicopter, per close monitoring cycle. Accomplishing a visual borescope inspection of the MGB bevel wheel as a result of an MGB magnetic plug inspection will take 1 work-hour for an estimated cost of $85 per helicopter. If necessary, replacing an epicyclic module will take 56 work-hours and parts will cost $50,524 (overhauled) for an estimated cost of $55,284 per module. If necessary, replacing a bevel reduction module will take 56 work-hours and parts will cost $18,500 (overhaled) for an estimated cost of $23,260 per module. Certain corrective action could vary significantly from helicopter to helicopter. The FAA has no data to determine the costs to accomplish the corrective action. <HD SOURCE="HD1">Authority for This Rulemaking</HD> Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority. The FAA is ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 23k characters. 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