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AD 2026-03704

Published 2026-02-24 · 5 models · 211 US-registered tails affected · Federal Register

Airworthiness Directives; The Boeing Company Airplanes Federal Register ↗

Abstract

The FAA proposes to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This proposed AD was prompted by reports that the low range radio altimeter (LRRA) system has an increased rate of non-computed data (NCD) outputs at low altitudes during approach and landing, which could cause unreliable altimeter function. This proposed AD would require replacing the left and right LRRA transmit and receive coaxial cables with larger gauge coaxial cables. The FAA is proposing this AD to address the unsafe condition on these products.

Applicability · by US fleet size

Federal Register text

Verbatim; the Federal Register publication is the legally binding document. Cite: 91 FR 8794. View on Federal Register ↗

[Federal Register Volume 91, Number 36 (Tuesday, February 24, 2026)] [Proposed Rules] [Pages 8794-8796] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2026-03704]

[[Page 8794]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2026-1335; Project Identifier AD-2025-00825-T] RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This proposed AD was prompted by reports that the low range radio altimeter (LRRA) system has an increased rate of non-computed data (NCD) outputs at low altitudes during approach and landing, which could cause unreliable altimeter function. This proposed AD would require replacing the left and right LRRA transmit and receive coaxial cables with larger gauge coaxial cables. The FAA is proposing this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by April 10, 2026.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: Federal eRulemaking Portal: Go to regulations.gov. Follow the instructions for submitting comments. Fax: 202-493-2251. Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2026-1335; 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 NPRM, any comments received, and other information. The street address for Docket Operations is listed above. Material Incorporated by Reference: For Boeing material identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website myboeingfleet.com. You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available at regulations.gov under Docket No. FAA-2026-1335.

FOR FURTHER INFORMATION CONTACT: Frank Carreras, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206- 231-3539; email: [email protected].