Airworthiness Directives; Robinson Helicopter Company Helicopters

41). This service information specifies procedures for revising the Pilot's Operating Handbook of affected helicopters by inserting the included “Special Tail Rotor Tip Preflight Inspection” page and briefing all pilots and maintenance personnel regarding those inspection procedures. This service information also specifies procedures for replacing, and returning or sending photos of affected TRBs to Robinson Helicopter Company. The FAA also reviewed Robinson Helicopter Company R22 Service Letter SL–93, R44 Service Letter SL–82, and R66 Service Letter SL–40, each dated June 30, 2021 (co-published as one document) (SL–93, SL–82, and SL–40). This service information specifies procedures for removing corrosion from TRBs, applying protectant, balancing TRBs after corrosion removal or painting, chemical cleaning TRBs, and tap testing the TRB tip cap area. Differences Between This AD and the Service Information The effectivity of Robinson Helicopter Company SB–120, SB–112, and SB–41 identify the helicopter S/Ns that the affected TRBs were factory-installed on and the shipping dates of affected TRB spares, whereas this AD applies to the specified model helicopters with certain part-numbered and serial- numbered TRBs installed. Robinson Helicopter Company SB–120, SB–112, and SB–41 specify revising the Pilot's Operating Handbook of affected helicopters and briefing all pilots and maintenance personnel regarding the inspection requirements, whereas this AD does not require those actions. Robinson Helicopter Company SB–120, SB–112, and SB–41 do not specify any visual inspections accomplished by a mechanic, whereas this AD requires repetitive visual inspections of the TRBs by persons authorized under 14 CFR 43.3. Robinson Helicopter Company SB–120, SB–112, and SB–41 specify replacing, and returning or sending photos of affected TRBs by December 31, 2024, whereas this AD requires removing affected TRBs from service within 10 months. 2/27/24, 8:52 AM about:blank about:blank 4/8 SL–93, SL–82, and SL–40 specify procedures for chemical cleaning TRBs, tap testing the TRB tip care area, applying protectant, and balancing TRBs after corrosion removal or painting, whereas this AD does not require those actions. Costs of Compliance The FAA estimates that this AD affects 2,701 helicopters of U.S. registry. The FAA estimates the following costs to comply with this AD. Labor costs are estimated at $85 per work-hour. Visually checking or inspecting the TRBs (up to two affected TRBs per helicopter) will take approximately 0.25 work-hour for an estimated cost of up to $22 per helicopter per cycle, for a U.S fleet cost of up to $59,422 per cycle. If required, removing any corrosion will take approximately 2 work-hours and the parts will cost approximately $100 for an estimated cost of $270 per TRB. Replacing a TRB will take approximately 3.5 work-hours and the parts will cost up to approximately $3,600 for an estimated cost of up to $3,898 per TRB. The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. Authority for This Rulemaking 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 issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. For the reasons discussed above, I certify that this AD: (1) Is not a “significant regulatory action” under Executive Order 12866, (2) Will not affect intrastate aviation in Alaska, and (3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. List of Subjects in 14 CFR Part 39 2/27/24, 8:52 AM about:blank about:blank 5/8 § 39.13 [Amended] Air transportation Aircraft Aviation safety Incorporation by reference Safety The Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. The FAA amends § 39.13 by adding the following new airworthiness directive: 2024–04–02 Robinson Helicopter Company: Amendment 39–22681; Docket No. FAA– 2023–2232; Project Identifier AD–2023–00943–R. (a) Effective Date This airworthiness directive (AD) is effective April 2, 2024. (b) Affected ADs None. (c) Applicability This AD applies to the Robinson Helicopter Company helicopters, certificated in any category, identified in paragraphs (c)(1) through (3) of this AD. (1) Model R22, R22 Alpha, R22 Beta, and R22 Mariner helicopters with tail rotor blade (TRB) part number (P/N) A029–2 with TRB serial numbers (S/N) up to 11279 inclusive (P/N A029–2 REV A through U inclusive), installed; (2) Model R44 and R44 II helicopters with TRB P/N C029–3 with TRB S/N up to 14329 inclusive (P/N C029–3 REV A through Q inclusive), installed; and (3) Model R66 helicopters with TRB P/N F029–1 with TRB S/N up to 3099 inclusive (P/N F029–1 REV A through F inclusive), installed. (d) Subject Joint Aircraft System Component (JASC) Code 6410, Tail Rotor Blades. ▪ ▪ ▪ ▪ ▪ 1. 2. 2/27/24, 8:52 AM about:blank about:blank 6/8 (e) Unsafe Condition This AD was prompted by reports of helicopters losing a TRB tip cap. The FAA is issuing this AD to detect and prevent TRB tip cap failures. The unsafe condition, if not addressed, could result in increased vibrations, reduced controllability, and subsequent loss of control of the helicopter. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions (1) Within 10 hours time-in-service (TIS) after the effective date of this AD and thereafter before the first flight of each day, visually check each TRB tip cap area (at and adjacent to the tip cap bond line on each surface and edge of the TRB) for an exposed tip cap bond line or bubbled paint, as depicted in Figure 1 to paragraph (g)(1) of this AD. These items may indicate evidence of corrosion. The owner/operator (pilot) holding at least a private pilot certificate may accomplish this TRB tip cap check and must enter compliance with this paragraph of the AD into the helicopter maintenance records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The record must be maintained as required by 14 CFR 91.417, 121.380, or 135.439. Figure 1 to Paragraph (g)(1)—TRB Tip Cap Check/Inspection (2) Within 100 hours TIS or during the next 100 hour or annual inspection after the effective date of this AD, whichever occurs first, and thereafter at intervals not to exceed 100 hours TIS or during the next 100 hour or annual inspection, whichever occurs first, visually inspect each TRB tip cap area (at and adjacent to the tip cap bond line on each surface and edge of the TRB) for evidence of corrosion, which may be indicated by an exposed tip cap bond line or bubbled paint, as depicted in Figure 1 to paragraph (g)(1) of this AD. (3) As a result of the actions required by either paragraph (g)(1) or (2) of this AD, if there is evidence of corrosion, an exposed tip cap bond line, or bubbled paint, before further flight, remove all of the 2/27/24, 8:52 AM about:blank about:blank 7/8 corrosion. Note 1 to paragraph (g)(3): Robinson Helicopter Company R22 Service Letter SL–93, R44 Service Letter SL–82, and R66 Service Letter SL–40, each dated June 30, 2021 (co-published as one document), provide information regarding removing corrosion from TRBs. (4) Within 10 months of the effective date of this AD, remove all TRBs identified in paragraph (c) of this AD from service. (5) As of 10 months after the effective date of this AD, do not install a TRB identified in paragraph (c) of this AD on any helicopter. (h) Alternative Methods of Compliance (AMOCs) (1) The Manager, West Certification Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the West Certification Branch, send it to the attention of the person identified in paragraph (i)(1) of this AD. Information may be emailed to: 9-ANM-LAACO- AMOC-REQUESTS@faa.gov. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. (i) Additional Information (1) For more information about this AD, contact James Guo, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: (562) 627–5357; email: james.guo@faa.gov. (2) For service information identified in this AD that is not incorporated by reference, contact Robinson Helicopter Company, Technical Support Department, 2901 Airport Drive, Torrance, CA 90505; phone (310) 539–0508; fax (310) 539–5198; email ts1@robinsonheli.com; or website robinsonheli.com. You may view this service information 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. (j) Material Incorporated by Reference None. Issued on February 13, 2024. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2024–03920 Filed 2–26–24; 8:45 am] 2/27/24, 8:52 AM about:blank about:blank 8/8 BILLING CODE 4910–13–P Date: See digital signature In Reply Refer To: 772-25-00024 Mr. Stephen Turnour Robinson Helicopter Company 2901 Airport Drive Torrance, California 90505 References: (1) Robinson Helicopter Company (RHC) Request Letter 66-25-01-02 dated January 13, 2025, COS - AMOC Request -Robinson AD 2024-04-02, with Enclosures (2) RHC Report RTR 635, Revision J, dated March 08, 2024 Dear Mr. Turnour: Subject: Approval of Global Alternative Method of Compliance (AMOC) to AD 2024- 04-02 for Robinson Helicopter Company R22, R22 Alpha, R22 Beta, R22 Mariner, R44, R44 II, R66 Helicopters The Federal Aviation Administration (FAA) has received your reference (1) letter proposing an AMOC to paragraph (g)(4) of AD 2024-04-02. AD 2024-04-02 addresses corrosion of tail rotor blade (TRB) tip caps that could cause debonding and liberation of the TRB tip cap. Affected aircraft and TRB are identified in paragraph (c) of AD 2024-04-02. Paragraph (g)(4) requires all TRB identified in paragraph (c) to be removed from service 10 months after the effective date of AD 2024-04-02. RHC has identified that recent production rates would not allow the current fleet of affected aircraft to comply in time with the AD. You are proposing as an AMOC to paragraph (g)(4) of AD 2024-04-02, to extend the compliance time 5 additional months (15 months after the effective date of the AD) to remove all TRBs identified in paragraph (c) of AD 2024-04-02 from service. This is under the condition that until removal from service, a repeat 10x visual maintenance inspection for corrosion along the TRB tip cap bond line at the leading edge, trailing edge, inboard and outboard surfaces is performed every 15 calendar days, and any evidence of corrosion must be removed before further flight. The FAA has reviewed your request and finds that your proposal provides an acceptable level of safety with regards to the requirements of paragraph (g)(4) of AD 2024-04-02. This determination was based on your reference (2) substantiation detailing the development of corrosion of the tip cap material along with FAA evaluation of the safety determination and risk evaluations used in the development of AD 2024-04-02. This 5-month extension however is the limit that the FAA can extend the compliance to paragraph (g)(4) of AD 2024-04-02 and no further extensions using any type of visual inspection will be granted as a global AMOC. Aviation Safety Aircraft Certification Service Compliance & Airworthiness Division West Certification Branch 3960 Paramount Boulevard, Suite 100 Lakewood, CA 90712-4102 772-25-00024 2 The FAA approves your AMOC proposal to paragraph (g)(4) of AD 2024-04-02, to extend the compliance time by 5 additional months (15 months after the effective date of the AD) under the condition that a repeat 10x visual maintenance inspection for corrosion along the tip cap bond line is performed at all the following locations: At the leading edge of the TRB tip cap bond line On the inboard surface of the TRB tip cap bond line On the outboard surface of the TRB tip cap bond line At the trailing edge of the TRB tip cap bond line Corrosion may be indicated by an exposed tip cap bond line or bubbled paint as identified in Figure 1 of paragraph (g)(1) of AD 2024-04-02. This inspection is to be repeated every 15 calendar days until the affected TRB is removed from service. If there is evidence of corrosion, an exposed tip cap bond line, or bubbled paint, before further flight, remove all the corrosion. The following limitations apply to this AMOC: All provisions of AD 2024-04-02 that are not specifically referenced above remain fully applicable and must be complied with accordingly. This approval is applicable to Robinson Helicopter Company R22, R22 Alpha, R22 Beta, R22 Mariner, R44, R44 II, R66 helicopters identified within the applicability of AD 2024-04-02 Affected tail rotor blades identified in paragraph (c) of AD 2024-04-02 must be removed from service within 15 months after the effective date of AD 2024-04-02. This FAA AMOC is transferable with the aircraft to another owner/operator. Before using this AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local Flight Standards District Office/Certificate Holding District Office. The preceding paragraph also applies to any applicable foreign-registered aircraft upon transfer of the aircraft to the U.S. registry if compliance with the AMOC has not been accomplished. This AMOC only applies to the FAA AD listed above. The FAA does not have the authority to approve this as an AMOC to any AD issued by another civil aviation authority (CAA). Approval of an AMOC to another CAA’s AD must come from that CAA. A copy of this response will be forwarded to the CAA where these aircraft are registered for their consideration. 772-25-00024 3 If you have any questions, or need additional information, please contact James Guo at (562) 627-5357 or email at james.guo@faa.gov. Sincerely, for Gregory S. DiLibero Manager, West Certification Branch Compliance & Airworthiness Division Aircraft Certification Service