2022-27805

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-2022-0588; Project Identifier AD-2022-00114-T; Amendment 39-22249; AD 2022-24-09] • RIN 2120-AA64 AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2021-14-20, which applied to all The Boeing Company Model 737 airplanes. AD 2021-14-20 required repetitive functional tests of the cabin altitude pressure switches, and on-condition actions, including replacement, if necessary. AD 2021-14-20 also required reporting test results. This AD was prompted by data collected from the reports required by AD 2021-14-20, which revealed that the switches were subject to false test failures due to lack of clear instructions for setup of the test adapters during the functional tests. This AD retains the repetitive functional tests and on-condition actions, and specifies certain adapter requirements for the functional tests. The FAA is issuing this AD to address the unsafe condition on these products. DATES: This AD is effective January 26, 2023. ADDRESSES: AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2022-0588; 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: Nicole Tsang, Aerospace Engineer, Cabin Safety and Environmental Systems Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3959; email: Nicole.S.Tsang@faa.gov. SUPPLEMENTARY INFORMATION: Background The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2021-14-20, Amendment 39-21647 (86 FR 38214, July 20, 2021) (AD 2021-14-20). AD 2021-14-20 applied to all The Boeing Company Model 737 airplanes. The NPRM published in the Federal Register on July 7, 2022 (87 FR 40460). The NPRM was prompted by reports of latent failures of the cabin altitude pressure switches, and the determination that using certain adapters while performing a functional test may lead to false failures of the cabin altitude pressure switches. In the NPRM, the FAA proposed to retain the repetitive functional tests and on-condition actions, and specify certain adapter requirements for the functional tests. The FAA is issuing this AD to address the unexpectedly high rate of latent failure of both pressure switches on the same airplane, which could result in the cabin altitude warning system not activating if the cabin altitude exceeds 10,000 feet, resulting in hypoxia of the flightcrew, and loss of control of the airplane. Discussion of Final Airworthiness Directive Comments The FAA received a comment from the Air Line Pilots Association (ALPA), who supported the NPRM without change. The FAA received additional comments from four commenters, including United Airlines, Delta Air Lines, American Airlines, and Boeing. The following presents the comments received …

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