2026-22383·DEPARTMENT OF TRANSPORTATION

Airworthiness Directives; The Boeing Company Airplanes

Proposed RuleComment Period OpenComments open

Published: Nov 3, 2026
Comments close: Dec 18, 2026
Citation: 91 FR 69227
Docket: Docket No. FAA-2026-11821, Project Identifier AD-2026-00567-T
Agencies: DEPARTMENT OF TRANSPORTATION, Federal Aviation Administration

Notice of proposed rulemaking (NPRM).

Summary

The Federal Aviation Administration (FAA) is proposing a new Airworthiness Directive (AD) that would replace an earlier AD issued in 2024 for certain Boeing 757 airplanes. The earlier directive required the installation of new relays and the rewiring of bundles that control the power‑transfer unit (PTU) valve. Since then, the FAA has discovered errors in the service bulletin that the 2024 AD relied on; those mistakes can either stop the required work from being completed correctly or create new safety hazards. The new proposal would correct those errors by specifying the proper relays, connectors, wiring changes, an operational test, and any follow‑up actions needed to ensure the PTU functions safely. The regulation is issued by the Department of Transportation’s FAA and applies to operators of the affected Boeing 757 models that fall under the original AD’s scope. It is aimed at airlines, leasing companies, and maintenance organizations that must keep these aircraft in compliance with safety standards. The notice was published on November 3, 2026, and the proposal becomes effective immediately, but the FAA will not finalize the rule until after a public comment period that ends on December 18, 2026. Interested parties can submit written comments, data, or arguments about the proposed requirements. After the comment deadline, the FAA will review the input, possibly revise the directive, and then issue a final AD that operators will be required to follow within the timeframes specified in the final rule.

AI-generated summary — verify against the Federal Register text.

Official abstract

The FAA proposes to supersede Airworthiness Directive (AD) 2024-25-09, which applies to certain The Boeing Company Model 757 airplanes. AD 2024-25-09 requires installing new relays and changing certain wire bundles leading to the power transfer unit (PTU) control valve. Since the FAA issued AD 2024-25-09, the FAA determined that the requirements bulletin mandated by AD 2024-25-09 contains errors. In some cases, those errors prevent the actions required by AD 2024-25-09 from being fully accomplished. In other cases, the errors would allow actions that could introduce new hazards affecting the operation and thus the availability of the PTU. This proposed AD would require, depending on the airplane configuration, installing new relays and new connectors, changing certain wire bundles, doing an operational test, and applicable on-condition actions. The FAA is proposing this AD to address the unsafe condition on these products.