AD 2026-20-02

Airworthiness directive · Air · Boeing 787-8, 787-9, Trent 1000-A and 17 more

Effective
October 14, 2026
Published
September 29, 2026 · 91 FR 61302–61304
Issued
September 24, 2026
Models
787-8, 787-9, Trent 1000-A, Trent 1000-A2, Trent 1000-AE, Trent 1000-AE2 and 14 more
Registered aircraft
193 matched by model
Product
Aircraft · Large airplane
ATA chapter
75 · Engine air
Amendment
39-23475
Docket
FAA-2026-11785
Project
AD-2026-00916-T
Issued as
Final rule; request for comments

Unofficial copy from the Federal Register XML, document 2026-19956. Only the govinfo PDF is the legal edition. DRS record last changed September 29, 2026.

On this page

Summary

The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 787-8 and 787-9 airplanes. This AD was prompted by a report of the lack of data to substantiate engine operability when an airplane is dispatched under a certain master minimum equipment list (MMEL) item. This AD prohibits dispatching an airplane under the operational procedures of the operator's minimum equipment list item corresponding to a certain MMEL item. The FAA is issuing this AD to address the unsafe condition on these products.

The airworthiness directive

2026-20-02 The Boeing Company: Amendment 39-23475; Docket No. FAA-2026-11785; Project Identifier AD-2026-00916-T.

(a) Effective Date

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This airworthiness directive (AD) is effective October 14, 2026.

(b) Affected ADs

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None.

(c) Applicability

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This AD applies to The Boeing Company Model 787-8 and 787-9 airplanes, certificated in any category, equipped with Rolls-Royce Deutschland Ltd & Co KG Model Trent 1000-A, Trent 1000-A2, Trent 1000-AE, Trent 1000-AE2, Trent 1000-C, Trent 1000-C2, Trent 1000-CE, Trent 1000-CE2, Trent 1000-D, Trent 1000-D2, Trent 1000-E, Trent 1000-G, Trent 1000-G2, Trent 1000-H, Trent 1000-H2, Trent 1000-J2, Trent 1000-K2, and Trent 1000-L2 engines.

(d) Subject

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Air Transport Association (ATA) of America Code 75, Air.

(e) Unsafe Condition

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This AD was prompted by a report that there is no data to substantiate engine operability, including compressor stability, relight capability, surge recovery, and inclement weather capability, when an airplane is dispatched under Master Minimum Equipment List (MMEL) item 75-33-01. The FAA is issuing this AD to address the risk of MMEL dispatch with an inoperative engine intermediate pressure bleed valve (IPBV) on one or both engines. The unsafe condition, if not addressed, could result in loss of engine thrust control and consequent loss of control of the airplane.

(f) Compliance

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

(g) Dispatch Prohibitions

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As of 60 days after the effective date of this AD: No person may dispatch an airplane under the operational procedures of the operator's minimum equipment list item corresponding to MMEL 75-33-01 (“Engine Intermediate Pressure (IP) Bleed Valves (RR)”).

(h) Alternative Methods of Compliance (AMOCs)

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(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 (i) 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.

(i) Additional Information

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For more information about this AD, contact Shaan Brar, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3558; email: shaan.s.brar@faa.gov.

(j) Material Incorporated by Reference

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None.

Rule preamble

The FAA’s background, reasoning and cost estimate, published with the AD.

DatesPage 1

This AD is effective October 14, 2026. The FAA must receive comments on this AD by November 13, 2026

AddressesPage 1

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 by searching for and locating Docket No. FAA-2026-11785; 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 street address for Docket Operations is listed above.

For further information contactPage 1

Shaan Brar, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3558; email: shaan.s.brar@faa.gov.

Comments invitedPage 1

The FAA invites you to send any written data, views, or arguments about this final rule. Send your comments using a method listed under the ADDRESSES section. Include Docket No. FAA-2026-11785 and Project Identifier AD-2026-00916-T at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, 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 final rule 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 final rule.

Confidential business informationPage 1

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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Shaan Brar, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3558; email: shaan.s.brar@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.

BackgroundPage 1

The FAA received a report from Rolls-Royce Deutschland Ltd & Co KG of the lack of data to substantiate engine operability, including compressor stability, relight capability, surge recovery, and inclement weather capability, when Model 787-8 and 787-9 airplanes equipped with certain Rolls-Royce Deutschland Ltd & Co KG engines are dispatched under MMEL item 75-33-01. MMEL item 75-33-01 (“Engine Intermediate Pressure (IP) Bleed Valves (RR)”) allows an aircraft to be dispatched for three days with one intermediate pressure bleed valve (IPBV) inoperative on each engine, provided appropriate performance adjustments are applied. The FAA is issuing this AD to address the risk of MMEL dispatch with an inoperative engine IPBV on one or both engines. This condition, if not addressed, could result in loss of engine thrust control and consequent loss of control of the airplane.

FAA's DeterminationPage 1

The FAA is issuing this AD because the agency has determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

AD RequirementsPage 1

This AD prohibits dispatching an airplane under the operational procedures of the operator's minimum equipment list item corresponding to MMEL item 75-33-01.

Justification for Immediate Adoption and Determination of the Effective DatePage 1

Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq.) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause.

An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because dispatching an airplane with an inoperative engine IPBV could result in loss of engine thrust control and consequent loss of control of the airplane. The FAA has determined that due to the lack of substantiating data, Model 787-8 and 787-9 airplanes equipped with certain Rolls-Royce Deutschland Ltd & Co KG engines dispatched with an inoperative IPBV are not assured to provide recovery from surges or flameouts or maintain continued operation under any anticipated operating environment. An airplane dispatched under MMEL item 75-33-01 with an inoperative IPBV on both engines could experience a loss of thrust control on both engines. An airplane dispatched with an inoperative IPBV on a single engine could experience a loss of thrust control on the engine with the inoperative IPBV, which would leave the airplane a single failure away from a catastrophic outcome (loss of the remaining engine due to any cause).

Additionally, the compliance time in this AD is shorter than the time necessary for the public to comment and for publication of the final rule. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b).

Regulatory flexibility actPage 2

The requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required.

Costs of CompliancePage 2

The FAA estimates that this AD affects 16 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

Estimated costs
ActionLabor costParts costCost per productCost on U.S. operators
Dispatch prohibition1 work-hour × $85 per hour = $85$0$85$1,360
Authority for This RulemakingPage 2

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 findingsPage 2

This AD will not have federalism implications under Executive Order 13132. This AD will 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 that this AD:

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

(2) Will not affect intrastate aviation in Alaska.

The amendmentPage 2

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

Adoption of the amendmentPage 2

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

2. The FAA amends § 39.13 by adding the following new airworthiness directive:

Affected TCDS · 2

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 193

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

193 by airframe model · 17 by engine model

By aircraft maker
  • Boeing193 aircraft
By year built
20102026
Registered aircraft by year built: 176 aircraft
20102
20126
20135
201413
201530
201617
201719
201810
20193
202014
20213
20229
20235
20246
202522
202612

17 with no year recorded

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Aircraft

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