2022-19936

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-2022-0872; Project Identifier AD-2022-00431-R; Amendment 39-22181; AD 2022-19-12] • RIN 2120-AA64 AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2021-19-08, which applied to certain Robinson Helicopter Company (Robinson) Model R44 and R44 II helicopters. AD 2021-19-08 required checking each tail rotor blade (blade) for any crack and removing any cracked blade from service. AD 2021-19-08 also required removing all affected blades from service and prohibited installing any affected blade on any helicopter. Since the FAA issued AD 2021-19-08, it was determined that an additional model helicopter and additional blades are affected by the unsafe condition. This AD requires the same actions as AD 2021-19-08 and adds certain Robinson Model R66 helicopters to the applicability and adds additional part-numbered and serial-numbered blades to the applicability. The FAA is issuing this AD to address the unsafe condition on these products. DATES: This AD is effective October 20, 2022. ADDRESSES: AD Docket: You may examine the AD docket at regulations.gov by searching for and locating Docket No. FAA-2022-0872; 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, 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. FOR FURTHER INFORMATION CONTACT: James Guo, Aerospace Engineer, Airframe Section, Los Angeles ACO Branch, Compliance & Airworthiness Division, FAA, 3960 Paramount Blvd., Lakewood, CA 90712; telephone (562) 627-5357; email james.guo@faa.gov. SUPPLEMENTARY INFORMATION: Background The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2021-19-08, Amendment 39-21726 (86 FR 49915, September 7, 2021) (AD 2021-19-08). AD 2021-19-08 applied to Robinson Model R44 and R44 II helicopters with a blade part number (P/N) C029-3 with serial number (S/N) 9410 through 9909 inclusive, installed. The NPRM published in the Federal Register on July 13, 2022 (87 FR 41627). The NPRM was prompted by reports of spanwise cracks found along the leading edge of P/N C029-3 blades, S/N 9410 through 9909. These affected blades were factory-installed or shipped as spares between March and December 2019. The cracks were found at different inspection intervals ranging from preflight inspections to 100-hour inspections. In one instance, a cracked blade was suspected when the pilot felt abnormal vibrations during flight; subsequent investigation determined that the blade was cracked. The cause of the cracks was determined to be a manufacturing defect in the properties of the blade skin that makes the blades prone to stress corrosion cracking. The NPRM was also prompted by a determination after AD 2021-19-08 was issued that an additional model helicopter and additional blades are affected by the unsafe condition. This condition, if not addressed, could result in reduced controllability and subsequent loss of control of the helicopter. AD 2021-19-08 r…

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