FAA Proposed Airworthiness Directive for Boeing 787 Airplanes

Content

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede Airworthiness Directive (AD) 2019-20-07, which applies to all The Boeing Company Model 787-8,
787-9, and 787-10 airplanes. AD 2019-20-07 requires repetitive operational checks of the leading edge (LE) outboard (OB) slats
and applicable on-condition actions. AD 2019-20-07 also requires revising the airplane flight manual (AFM) to prohibit flap
retraction under icing conditions and revising the existing maintenance or inspection program, as applicable, to incorporate
a new operation check. Since the FAA issued AD 2019-20-07, the manufacturer developed further actions to address the unsafe
condition. This proposed AD would retain all requirements of AD 2019-20-07 and would require replacing the LE outboard geared
rotary actuator (GRA) with a LE outboard lockout actuator (LEOLA) at leading edge OB slat locations and revising the existing
maintenance or inspection program, as applicable, to incorporate a new certification maintenance requirement (CMR). This proposed
AD would also remove airplanes from the applicability. 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 May 4, 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-2026-2712; 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-2026-2712.

FOR FURTHER INFORMATION CONTACT:

Emanuel Chaves Torres, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5350; email: emanuel.chaves.torres@faa.gov.

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-2026-2712; Project Identifier AD-2025-00931-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
Emanuel Chaves Torres, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5350; email: emanuel.chaves.torres@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 2019-20-07, Amendment 39-19760 (84 FR 54765, October 11, 2019) (AD 2019-20-07), for all The Boeing Company
Model 787-8, 787-9, and 787-10 airplanes. AD 2019-20-07 was prompted by a determination that the LE OB slat system could be
out of position without flight deck annunciation. AD 2019-20-07 requires repetitive operational checks of the LE OB slats
and applicable on-condition actions. AD 2019-20-07 also requires revising the AFM to prohibit flap retraction under icing
conditions and revising the existing maintenance or inspection program, as applicable, to incorporate a new operation check.
The agency issued AD 2019-20-07 to address a potential condition in which the LE OB slat system could be out of position without
flight deck annunciation. This condition, if not addressed, could result in insufficient lift, resulting in inability to maintain
continued safe flight and landing.

Actions Since AD 2019-20-07 Was Issued

The preamble to AD 2019-20-07 specifies that the FAA considers that AD “interim action” and that the FAA may consider further
rulemaking. Since the FAA issued AD 2019-20-07, the manufacturer has developed final actions to address the unsafe condition.
The FAA has determined that these final actions must be required to address the unsafe condition and that accomplishing the
final actions will terminate the requirements of AD 2019-20-07. The manufacturer has also incorporated these final actions
on airplanes in production, which reduces the number of airplanes that would be affected by the unsafe condition.

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 B787-81205-SB270055-00 RB, Issue 002, dated November 25, 2024. This material
specifies procedures for replacing the LE outboard GRA with a LEOLA at leading edge slat 2 and slat 11 outboard locations
and revising the operator's maintenance program to incorporate CMR document item 27-CMR-14, “Functionally check the Leading
Edge Power Drive Unit Half System Torque Brake.”

This proposed AD would also require Boeing Alert Requirements Bulletin B787-81205-SB270051-00 RB, Issue 001, dated July 5,
2019, which the Director of the Federal Register approved for incorporation by reference as of October 11, 2019 (84 FR 54765,
October 11, 2019).

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 retain all requirements of AD 2019-20-07. This proposed AD would remove airplanes from the applicability
by specifying affected line numbers and require new actions that would terminate the requirements of AD 2019-20-07. This proposed
AD would also 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-2026-2712.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 174 airplanes of U.S. registry. The FAA estimates the
following costs to comply with this proposed AD:

| Action | Labor cost | Parts cost | Cost per product | Cost on U.S. operators |
| --- | --- | --- | --- | --- |
| Repetitive operational checks (retained actions from AD 2019-20-07) | 8 work-hours × $85 per hour = $680 per operational check | $0 | $680 per operational check | $118,320 per operational check. |
| AFM revision (retained action from AD 2019-20-07) | 1 work-hour × $85 per hour = $85 | 0 | $85 | $14,790. |
| Replacement (new proposed action) | 9 work-hours × $85 per hour = $765 | 31,610 | $32,375 | $5,633,250. |
| * Table does not include estimated costs for revising the existing maintenance or inspection program. | | | | |
The FAA has determined that revising the existing maintenance or inspection program takes an average of 90 work-hours per
operator, although the agency recognizes that this number may vary from operator to operator. Since operators incorporate
maintenance or inspection program changes for their affected fleet(s), the FAA has determined that a per-operator estimate
is more accurate than a per-airplane estimate. Therefore, the agency estimates the average total cost per operator to be $7,650
(90 work-hours × $85 per work-hour).

The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs
of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators.

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.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

The Proposed Amendment

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

PART 39—AIRWORTHINESS DIRECTIVES

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

Authority:

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

§ 39.13 [Amended] 2. The FAA amends § 39.13 by:

a. Removing Airworthiness Directive (AD) 2019-20-07, Amendment 39-19760 (84 FR 54765, October 11, 2019), and

b. Adding the following new AD:

The Boeing Company:
Docket No. FAA-2026-2712; Project Identifier AD-2025-00931-T.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by May 4, 2026.

(b) Affected ADs

This AD replaces AD 2019-20-07, Amendment 39-19760 (84 FR 54765, October 11, 2019) (AD 2019-20-07).

(c) Applicability

This AD applies to The Boeing Company Model 787-8, 787-9, and 787-10 airplanes, certificated in any category, as identified
in Boeing Alert Requirements Bulletin B787-81205-SB270055-00 RB, Issue 002, dated November 25, 2024.

(d) Subject

Air Transport Association (ATA) of America Code 27, Flight Controls.

(e) Unsafe Condition

This AD was prompted by a determination that the leading edge (LE) outboard (OB) slat system could be out of position without
flight deck annunciation. The FAA is issuing this AD to address a potential condition in which the LE OB slat system could
be out of position without flight deck annunciation. The unsafe condition, if not addressed, could result in insufficient
lift, resulting in inability to maintain continued safe flight and landing.

(f) Compliance

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

(g) Retained Required Actions, With No Changes

This paragraph restates the requirements of paragraph (g) of AD 2019-20-07, with no changes. Except as specified by paragraph
(h) of this AD: At the applicable times specified in the “Compliance” paragraph of Boeing Alert Requirements Bulletin B787-81205-SB270051-00
RB, Issue 001, dated July 5, 2019, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions
of Boeing Alert Requirements Bulletin B787-81205-SB270051-00 RB, Issue 001, dated July 5, 2019.

Note 1 to paragraph (g):
Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin B787-81205-SB270051-00,
Issue 001, dated July 5, 2019, which is referred to in Boeing Alert Requirements Bulletin B787-81205-SB270051-00 RB, Issue
001, dated July 5, 2019.

(h) Retained Exception to Service Information Specifications, With No Changes

This paragraph restates the requirements of paragraph (h) of AD 2019-20-07, with no changes. For purposes of determining compliance
with the requirements of this AD: Where Boeing Alert Requirements Bulletin B787-81205-SB270051-00 RB, Issue 001, dated July
5, 2019, uses the phrase “the Issue 001 date of Requirements Bulletin B787-81205-SB270051-00 RB,” this AD requires using “October
11, 2019” (the effective date of AD 2019-20-07).

(i) Retained Airplane Flight Manual (AFM) Revision To Prohibit Flap Retraction Under Icing Conditions, With No Changes

This paragraph restates the requirements of paragraph (i) of AD 2019-20-07, with no changes. Within 60 days after October
11, 2019 (the effective date of AD 2019-20-07), revise the Limitations Section of the existing AFM to include the information
in figure 1 to paragraph (i) of this AD. This may be done by inserting a copy of figure 1 to paragraph (i) of this AD into
the Limitations Section of the existing AFM.

Figure 1 to Paragraph (i): AFM Revision

(j) Retained Maintenance or Inspection Program Revision To Incorporate a New Operation Check, With No Changes

This paragraph restates the requirements of paragraph (j) of AD 2019-20-07, with no changes. Within 60 days after October
11, 2019 (the effective date of AD 2019-20-07), revise the existing maintenance or inspection program, as applicable, to incorporate
the information specified in figure 2 to paragraph (j) of this AD. This may be done by inserting a copy of figure 2 to paragraph
(j) of this AD into the existing maintenance or inspection program.

BILLING CODE 4910-13-P

Figure 2 To Paragraph (j): Maintenance or Inspection Program Revision

BILLING CODE 4910-13-C

(k) Retained No Alternative Actions or Intervals, With No Changes

This paragraph restates the requirements of paragraph (k) of AD 2019-20-07, with no changes. After the existing maintenance
or inspection program has been revised as required by paragraph (j) of this AD, no alternative actions (e.g., inspections) or intervals may be used unless the actions or intervals are approved as an alternative method of compliance
(AMOC) in accordance with the procedures specified in paragraph (p) of this AD.

(l) New Required Actions

Except as specified by paragraph (i) of this AD: At the applicable times specified in the “Compliance” paragraph of Boeing
Alert Requirements Bulletin B787-81205-SB270055-00 RB, Issue 002, dated November 25, 2024, do all applicable actions identified
in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin B787-81205-SB270055-00 RB,
Issue 002, dated November 25, 2024.

Note 2 to paragraph (l):
Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin B787-81205-SB270055-00,
Issue 002, dated November 25, 2024, which is

  referred to in Boeing Alert Requirements Bulletin B787-81205-SB270055-00 RB, Issue 002, dated November 25, 2024.

(m) Terminating Action

Accomplishing the actions required by paragraph (l) of this AD terminates the requirements of paragraphs (g), (i), and (j)
of this AD for that airplane. After all affected airplanes in an operator's fleet have complied with paragraph (l) of this
AD, the AFM revision required by paragraph (i) of this AD may be removed and the maintenance or inspection program revision
required by paragraph (j) of this AD may be removed.

(n) Exceptions to Requirements Bulletin Specifications

Where the Compliance Time column of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin B787-81205-SB270055-00
RB, Issue 002, dated November 25, 2024, refers to the Issue 001 date of Requirements Bulletin B787-81205-SB270055-00 RB, this
AD requires using the effective date of this AD.

(o) Credit for Previous Actions

This paragraph provides credit for the actions specified in paragraph (l) of this AD, if those actions were performed before
the effective date of this AD using Boeing Alert Requirements Bulletin B787-81205-SB270055-00 RB, Issue 001, dated December
12, 2023.

(p) 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 Continued Operational
Safety Branch, send it to the attention of the person identified in paragraph (q)(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 2019-20-07 are approved as AMOCs for the corresponding provisions of paragraphs (g), (i), and (j)
of this AD.

(q) Additional Information

(1) For more information about this AD, contact Emanuel Chaves Torres, Aviation Safety Engineer, FAA, 2200 South 216th St.,
Des Moines, WA 98198; phone: 562-627-5350; email: emanuel.chaves.torres@faa.gov.

(2) Material identified in this AD that is not incorporated by reference is available at the address specified in paragraph
(r)(5) of this AD.

(r) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) 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 this AD specifies otherwise.

(3) The following material was approved for IBR on [DATE 35 DAYS AFTER PUBLICATION OF THE FINAL RULE].

(i) Boeing Alert Requirements Bulletin B787-81205-SB270055-00 RB, Issue 002, dated November 25, 2024.

(ii) [Reserved]

(4) The following material was approved for IBR on October 11, 2019 (84 FR 54765, October 11, 2019).

(i) Boeing Alert Requirements Bulletin B787-81205-SB270051-00 RB, Issue 001, dated July 5, 2019.

(ii) [Reserved]

(5) 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.

(6) 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.

(7) 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.

Issued on March 12, 2026. Lona C. Saccomando, Acting Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2026-05327 Filed 3-17-26; 8:45 am] BILLING CODE 4910-13-P

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