SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments using a method listed under the ADDRESSES section. Include “Docket No. FAA-2026-11821; Project Identifier AD-2026-00567-T” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments.

Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.

Confidential Business Information

CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Katherine Venegas, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5353; email: katherine.venegas@faa.gov. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

The FAA issued AD 2024-25-09, Amendment 39-22911 (90 FR 1850, January 10, 2025) (AD 2024-25-09), for certain The Boeing Company Model 757 airplanes. AD 2024-25-09 was prompted by reports of several occurrences of a PTU control valve that failed to open when commanded. AD 2024-25-09 requires installing new relays and changing certain wire bundles leading to the PTU control valve. The agency issued AD 2024-25-09 to address failure of the PTU control valve, which, in conjunction with a loss of the left engine or engine-driven pump during takeoff, may result in a failure of the landing gear to retract in a timely manner. This condition, if not addressed, could result in additional drag, a reduced climb gradient, and an inability to clear obstacles on takeoff. This condition can result in loss of continued safe flight and landing.

Actions Since AD 2024-25-09 Was Issued

An operator reported errors in the instructions of Boeing Alert Requirements Bulletin 757-29A0071 RB, dated November 16, 2023, that prevented its accomplishment on airplanes identified as Group 3 airplanes in that requirements bulletin. Since the FAA issued AD 2024-25-09, Boeing has identified additional errors affecting all of the groups in that requirements bulletin, including errors that would allow actions that could introduce new hazards.

The FAA assessed the new hazards. Although the agency quantitatively assessed the new hazards to be of relatively low risk, the FAA determined that they could affect the operation and thus the availability of the PTU. The PTU is required to operate as a safety system backup. The new hazards that the errors could introduce are therefore a safety concern. The original unsafe condition also remains, because the corrective action AD 2024-25-09 requires cannot be accomplished as intended on certain airplanes.

On April 6, 2026, the FAA issued Special Airworthiness Information Bulletin 2026-09 as an interim action to advise owners and operators of the errors and to recommend actions before AD 2024-25-09 is superseded by this proposed AD. Boeing has since issued Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026, to correct the errors.

The FAA also issued FAA letter 523-26-00077, dated April 29, 2026, to identify the applicable set of deviations approved as an alternative method of compliance (AMOC) to AD 2024-25-09. Accomplishing Boeing Alert Requirements Bulletin 757-29A0071 RB, dated November 16, 2023, in combination with the applicable AMOC specified in the FAA letter achieves a configuration consistent with Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026. ( printed page 69229)

FAA's Determination

The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.

Material Incorporated by Reference Under 1 CFR Part 51

The FAA reviewed Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026. This material specifies procedures for, depending on the airplane configuration, installing new relays and a new connector in the P33 panel, installing new connectors and changing certain wire bundles ( e.g., changing bundles leading to the PTU control valve, changing bundles between certain panels, changing bundles between certain panels and certain disconnect brackets, and other wire bundle changes that include installing a new wire bundle clamp and lacing tape on wire bundle W4236, changing the position of a wire bundle W4236 ground wire, installing white lacing tape on wire bundle W2514), and doing general visual inspections for correct wire bundle W2514 routing and for a missing seal ring at the right body fairing feedthru seal. This material also specifies applicable on-condition actions. On-condition actions include correcting the routing of wire bundle W2514 through the clamp aft of disconnect bracket AD0880, installing a seal ring at the right body fairing feedthru seal, and doing applicable corrective actions to address failed operational tests and repeating the operational test until the test passes.

This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

Proposed AD Requirements in This NPRM

This proposed AD would require accomplishing the actions specified in the material already described, except for any differences identified as exceptions in the regulatory text of this proposed AD.

For information on the procedures and compliance times, see this material at regulations.gov under Docket No. FAA-2026-11821.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 467 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:

The FAA estimates the following costs to do any necessary on-condition actions that would be required based on the results of the proposed general visual inspections and operational tests. The agency has no way of determining the number of aircraft that might need these on-condition actions.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority.

The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify this proposed regulation:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Would not affect intrastate aviation in Alaska, and

(3) Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

2. The FAA amends § 39.13 by: ( printed page 69230)

a. Removing Airworthiness Directive (AD) 2024-25-09, Amendment 39-22911 ( 90 FR 1850, January 10, 2025), and

b. Adding the following new AD:

The Boeing Company: Docket No. FAA-2026-11821; Project Identifier AD-2026-00567-T.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by December 18, 2026.

(b) Affected ADs

This AD replaces AD 2024-25-09, Amendment 39-22911 (90 FR 1850, January 10, 2025) (AD 2024-25-09).

(c) Applicability

This AD applies to The Boeing Company Model 757-200, -200PF, -200CB, and -300 series airplanes, certificated in any category, as identified in Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026.

(d) Subject

Air Transport Association (ATA) of America Code 29, Hydraulic power.

(e) Unsafe Condition

This AD was prompted by reports of several occurrences of a power transfer unit (PTU) control valve that failed to open when commanded, and the determination that errors in the service information required by AD 2024-25-09 prevent accomplishment of the actions on certain airplanes and would allow actions that could introduce new hazards affecting the operation and thus the availability of the PTU. The FAA is issuing this AD to address failure of the PTU control valve, which, in conjunction with a loss of the left engine or engine-driven pump during takeoff, may result in a failure of the landing gear to retract in a timely manner. The unsafe condition, if not addressed, could result in additional drag, a reduced climb gradient, and an inability to clear obstacles on takeoff, resulting in loss of continued safe flight and landing.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Required Actions

Except as specified by paragraph (h) of this AD: At the applicable times specified in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026.

Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 757-29A0071, Revision 1, dated May 28, 2026, which is referred to in Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026.

(h) Exceptions to Requirements Bulletin Specifications

Where the “Effectivity” paragraph and the Compliance Time columns of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026, refer to the Revision 1 date of Requirements Bulletin 757-29A0071 RB, this AD requires using the effective date of this AD.

(i) Credit for Previous Actions

This paragraph provides credit for the actions specified in paragraph (g) of this AD, if those actions were performed before the effective date of this AD using the material specified in paragraph (i)(1) of this AD in combination with the applicable alternative method of compliance (AMOC) specified in paragraph (i)(2) of this AD.

(1) Boeing Alert Requirements Bulletin 757-29A0071 RB, dated November 16, 2023, except where the figures in the Accomplishment Instructions of Boeing Alert Requirements Bulletin 757-29A0071 RB, dated November 16, 2023, specify certain positions on the P33 panel and disconnect bracket AD0880 or AD0881 for installing the connectors, this AD allows any open position on the P33 panel or disconnect bracket AD0880 or AD0881 for installing the connectors. Boeing Alert Requirements Bulletin 757-29A0071 RB, dated November 16, 2023, was incorporated by reference in AD 2024-25-09.

(2) The applicable set of deviations approved as an AMOC to AD 2024-25-09 and identified in the enclosure to FAA letter 523-26-00077, dated April 29, 2026, which is not incorporated by reference in this AD.

(j) Alternative Methods of Compliance (AMOCs)

(1) The Manager, AIR-520, Continued Operational Safety Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in paragraph (k)(1) of this AD. Information may be emailed to: AMOC@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office.

(2) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by The Boeing Company Organization Designation Authorization (ODA) that has been authorized by the Manager, AIR-520, Continued Operational Safety Branch, FAA, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(3) AMOCs approved for AD 2024-25-09 are approved as AMOCs for the corresponding provisions of Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026, that are required by paragraph (g) of this AD.

(k) Additional Information

(1) For more information about this AD, contact Katherine Venegas, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5353; email: katherine.venegas@faa.gov.

(2) Boeing material identified in this AD that is not incorporated by reference is available at the address specified in paragraph (l)(3) of this AD.

(3) FAA letter 523-26-00077 and its enclosure are located in the AD docket and may be viewed at regulations.gov under Docket No. FAA-2026-11821.

(l) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise.

(i) Boeing Alert Requirements Bulletin 757-29A0071 RB, Revision 1, dated May 28, 2026.

(ii) [Reserved]

(3) For Boeing material identified in this 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.

(4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA 98198. For information on the availability of this material at the FAA, call 206-231-3195.

(5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/​federal-register/​cfr/​ibr-locations or email fr.inspection@nara.gov.

91 FR 69227