2020-02446

Document Headings Document headings vary by document type but may contain the following: • the agency or agencies that issued and signed a document • the number of the CFR title and the number of each part the document amends, proposes to amend, or is directly related to • the agency docket number / agency internal file number • the RIN which identifies each regulatory action listed in the Unified Agenda of Federal Regulatory and Deregulatory Actions See the Document Drafting Handbook for more details. Department of Transportation Federal Aviation Administration • 14 CFR Part 39 • [Docket No. FAA-2019-0663; Product Identifier 2018-SW-057-AD; Amendment 39-21025; AD 2020-02-17] • RIN 2120-AA64 AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-70, S-70A, S-70C, S-70C(M), and S-70C(M1) helicopters. This AD was prompted by four incidents of disbonding between the tail rotor (T/R) blade pitch horn and the torque tube. This AD requires recurring visual and tap inspections of the T/R blade, and depending on the outcome, replacing the T/R blade. The FAA is issuing this AD to address the unsafe condition on these products. DATES: This AD is effective March 13, 2020. ADDRESSES: For service information related to this final rule, contact your local Sikorsky Field Representative or Sikorsky's Service Engineering Group at Sikorsky Aircraft Corporation, 124 Quarry Road, Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; email wcs_cust_service_eng.gr-sik@lmco.com. Operators may also log on to the Sikorsky 360 website at https://www.sikorsky360.com. You may view the related service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177. Examining the AD Docket You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2019-0663; 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 AD, the regulatory evaluation, any comments received, and other information. The street address for Docket Operations is Docket Operations, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12 140, 1200 New Jersey Avenue SE, Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Kristopher Greer, Aviation Safety Engineer, Boston ACO Branch, Compliance & Airworthiness Division, FAA, 1200 District Avenue, Burlington, MA 01803; telephone 781-238-7799; email kristopher.greer@faa.gov. SUPPLEMENTARY INFORMATION: Discussion The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to Sikorsky Model S-70, S-70A, S-70C, S-70C(M), and S-70C(M1) helicopters with T/R blade part number 70101-31000 (all dash numbers) and with a serial number up to and including A009-08915. The NPRM published in the Federal Register on September 6, 2019 (84 FR 46903). The NPRM was prompted by four incidents of disbonding between the T/R blade pitch horn and the torque tube on military-operated Model UH-60L and SH-60F helicopters. The disbonding produced minor to severe vibrations due to the mass imbalance. This condition may also occur on Sikorsky Model S-70, S-70A, S-70C, S-70C(M), and S-70C(M1) helicopters due to design similarity. Disbonding between the T/R blade pitch horn and the torque tube, if not addressed, could result in the T/R blade pitch horn rocking in the torque tube, leading to increased T/R vibrations. These vibrations could lead to crushing of the torque tube and su…

Fonte: Federal Register (federalregister.gov). Texto original em inglês. Conteúdo sanitizado por segurança.