Rule2026-22318
Airworthiness Directives; The Boeing Company Airplanes
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
November 2, 2026
Effective
December 7, 2026
Issuing agencies
Transportation DepartmentFederal Aviation Administration
Abstract
The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This AD was prompted by a report that, during production, certain sealant installations within the center wing fuel tank did not receive required visual and adhesion inspections. This AD requires a detailed inspection of certain sealant installations in the left, right, and center wing side-of-body areas, an adhesion test of the sealant, and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.
Full Text
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<title>Federal Register, Volume 91 Issue 210 (Monday, November 2, 2026)</title>
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[Federal Register Volume 91, Number 210 (Monday, November 2, 2026)]
[Rules and Regulations]
[Pages 68877-68879]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-22318]
[[Page 68877]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2026-1322; Project Identifier AD-2025-01665-T;
Amendment 39-23507; AD 2026-22-05]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain The Boeing Company Model 787-8, 787-9, and 787-10 airplanes.
This AD was prompted by a report that, during production, certain
sealant installations within the center wing fuel tank did not receive
required visual and adhesion inspections. This AD requires a detailed
inspection of certain sealant installations in the left, right, and
center wing side-of-body areas, an adhesion test of the sealant, and
applicable on-condition actions. The FAA is issuing this AD to address
the unsafe condition on these products.
DATES: This AD is effective December 7, 2026.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of December 7,
2026.
ADDRESSES:
AD Docket: You may examine the AD docket at <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-1322; 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 address for Docket Operations is U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
Material Incorporated by Reference:
<bullet> 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 <a href="http://myboeingfleet.com">myboeingfleet.com</a>.
<bullet> 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 <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-1322.
FOR FURTHER INFORMATION CONTACT: Tak Kobayashi, Aviation Safety
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-
231-3553; email: <a href="/cdn-cgi/l/email-protection#1e6a7f757f76776d7f3075717c7f677f6d76775e787f7f30797168"><span class="__cf_email__" data-cfemail="7602171d171e1f0517581d1914170f17051e1f3610171758111900">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Background
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain The Boeing
Company Model 787-8, 787-9, and 787-10 airplanes. The NPRM was
published in the Federal Register on February 24, 2026 (91 FR 8791).
The NPRM was prompted by a report that, during production, certain
sealant installations within the center wing fuel tank did not receive
required visual and adhesion inspections. In the NPRM, the FAA proposed
to require a detailed inspection of certain sealant installations in
the left, right, and center wing side-of-body areas, an adhesion test
of the sealant, and applicable on-condition actions. The FAA is issuing
this AD to address the potential for sealant defects.
Discussion of Final Airworthiness Directive
Comments
The FAA received comments from the Air Line Pilots Association,
International (ALPA), United Airlines, and an individual, who supported
the NPRM without change.
The FAA received additional comments from American Airlines
(American), Boeing, and the Foundation for Aviation Safety. The
following presents the comments received on the NPRM and the FAA's
response to each comment.
Request To Allow Alternative Repair Instructions
Boeing and American requested that the FAA add an exception to
paragraph (h) of the proposed AD that would allow certain repairs to be
accomplished using other Boeing service information. Specifically,
American requested that the fuel tank repairs be accomplished using the
Boeing 787 Aircraft Maintenance Manual (AMM), B787-A-28-11-00-14A-663A-
A, ``Fuel Tank Structure Sealant--Standard,'' instead of using a method
approved in accordance with the procedures in paragraph (i) of the
proposed AD. Boeing requested that the removal and replacement of
damaged sealant to restore edge seals, fillet seals, and seal caps be
performed using the critical design configuration control limitations
(CDCCLs) and airworthiness limitation instructions (ALIs) in the latest
published Boeing 787 Special Compliance Items/Airworthiness
Limitations, Document D011Z009-03-04. Boeing stated that critical
features of sealant are defined in that document, and that repairs
involving removal and replacement of damaged sealant, without any
deviation from that document, reliably restore the airworthiness of the
airplane.
The FAA agrees with Boeing's request. Sealant repairs that comply
with the requirements of all applicable airworthiness limitations
(AWLs) will restore the sealant installation intended by this AD and
therefore should be allowed without further FAA review under the
provisions of paragraph (i) of this AD. Accordingly, the FAA has
revised paragraph (h)(2) of this AD to specify that, for sealant
installation repairs, complying with AWL Nos. 28-AWL-83, 28-AWL-120,
28-AWL-121, 28-AWL-123, 28-AWL-124, and 28-AWL-125, as applicable, in
Section D, ``Summary List of AWLs,'' of Boeing 787 Special Compliance
Items/Airworthiness Limitations, D011Z009-03-04, dated August 2018, is
an acceptable repair. Further, the FAA notes that operators are allowed
to use the applicable AMM procedures for removal and replacement of
damaged sealant, provided each repair complies with the requirements of
all applicable AWL items associated with sealant installation.
Therefore, the FAA has not revised this AD in response to American's
comment.
Request To Clarify the Inspection Area
American requested that the FAA clarify the inspection area in
Figure 1, Appendix F of Boeing Alert Requirements Bulletin B787-81205-
SB570053-00 RB, Issue 001, dated November 5, 2025 (the Boeing Alert
Requirements Bulletin). American stated it is unclear whether the
specified adhesion test of the injection seals should be done along the
yellow dashed lines or within the whole area enclosed by those lines in
Figure 1. Further, American stated Figure 1 does not clearly identify
the area for inspecting the interface between sealant and substrate.
The FAA notes that Figure 1 of Appendix F of the Boeing Alert
Requirements Bulletin is an example of the actual inspection areas that
are provided in the Accomplishment Instructions of the Boeing Alert
Requirements Bulletin. For example, View J of ``Task 7 Figure 8'' shows
the adhesion test area, and Step 4 of ``Task
[[Page 68878]]
7 Figure 8'' requires an adhesion test of injection sealant in
accordance with Appendix F (as noted in footnote [5] to Table 1 of Task
7). Therefore, the adhesion test is required along the dashed lines
shown in Figure 1 of Appendix F. Further, paragraph 1.C of Appendix F
specifies the required sealant conditions at the transition from the
substrate. When the injection sealant is tested for adhesion, the
sealant transition from the substrate must be inspected in accordance
with Appendix F. The FAA has not changed this AD in this regard.
Request To Clarify Status of Installation Inspections During Production
The Foundation for Aviation Safety asked if the FAA has confirmed
that inspections of the installation job (i.e., sealant installation
within the center wing fuel tank) are now required during production.
The FAA notes the applicability of this AD is limited to certain
airplanes identified in paragraph (c) of the AD due to lack of evidence
substantiating that the required inspections were accomplished on those
airplanes during production. The FAA has confirmed that inspections of
the sealant installations within the center wing tank are being
performed during production on airplanes that are outside the
applicability of this AD. No change to this AD is necessary as a result
of this comment.
Conclusion
The FAA reviewed the relevant data, considered any comments
received, and determined that air safety requires adopting this AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these products. Except for minor editorial changes, and
any other changes described previously, this AD is adopted as proposed
in the NPRM. None of the changes will increase the economic burden on
any operator.
Material Incorporated by Reference Under 1 CFR Part 51
The FAA reviewed Boeing Alert Requirements Bulletin B787-81205-
SB570053-00 RB, Issue 001, dated November 5, 2025. This material
specifies procedures for a detailed inspection for any sealant defects
and any surface depression defects on identified sealant installed in
the left, right, and center wing side-of-body area and the area between
side-of-body rib and rib 2, an adhesion test on identified sealants
installed in the left, right, and center wing side-of-body area and the
area between side-of-body rib and rib 2, and applicable on-condition
actions. On-condition actions also include contacting Boeing for repair
instructions and performing a repair.
The FAA also reviewed Section D, ``Summary List of AWLs,'' of
Boeing 787 Special Compliance Items/Airworthiness Limitations,
D011Z009-03-04, dated August 2018. This material specifies the AWLs
(CDCCLs and ALIs) for the fuel system, including sealant installation
repair.
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.
Costs of Compliance
The FAA estimates that this AD affects 60 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
Estimated Costs
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Cost per Cost on U.S.
Action Labor cost Parts cost product operators
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Detailed inspection and adhesion test of 34 work-hours x $85 per $0 $2,890 $173,400
sealant. hour = $2,890.
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The FAA has received no definitive data on which to base the cost
estimates for the on-condition repairs specified in this AD.
The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some or all of the costs of
this 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
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,
(2) Will not affect intrastate aviation in Alaska, and
(3) Will 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 Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2026-22-05 The Boeing Company: Amendment 39-23507; Docket No. FAA-
2026-1322; Project Identifier AD-2025-01665-T.
(a) Effective Date
This airworthiness directive (AD) is effective December 7, 2026.
[[Page 68879]]
(b) Affected ADs
None.
(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-SB570053-00 RB, Issue
001, dated November 5, 2025.
(d) Subject
Air Transport Association (ATA) of America Code 57, Wing.
(e) Unsafe Condition
This AD was prompted by a report that, during production,
certain sealant installations within the center wing fuel tank
volume did not receive required visual and adhesion inspections. The
FAA is issuing this AD to address the potential for sealant defects.
The unsafe condition, if not addressed, could result in development
of an ignition source within the fuel tank volume and a risk of a
fuel tank explosion during a lightning strike event.
(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 B787-81205-SB570053-00 RB, Issue 001,
dated November 5, 2025, do all applicable actions identified in, and
in accordance with, the Accomplishment Instructions of Boeing Alert
Requirements Bulletin B787-81205-SB570053-00 RB, Issue 001, dated
November 5, 2025.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
B787-81205-SB570053-00, Issue 001, dated November 5, 2025, which is
referred to in Boeing Alert Requirements Bulletin B787-81205-
SB570053-00 RB, Issue 001, dated November 5, 2025.
(h) Exceptions to Requirements Bulletin Specifications
(1) Where the Compliance Time column of the table in the
``Compliance'' paragraph of Boeing Alert Requirements Bulletin B787-
81205-SB570053-00 RB, Issue 001, dated November 5, 2025, refers to
the Issue 001 date of Requirements Bulletin B787-81205-SB570053-00
RB, this AD requires using the effective date of this AD.
(2) Where Boeing Alert Requirements Bulletin B787-81205-
SB570053-00 RB, Issue 001, dated November 5, 2025, specifies
contacting Boeing for repair instructions, this AD requires doing
the repair using a method approved in accordance with the procedures
specified in paragraph (i) of this AD. For sealant installation
repairs: Complying with Airworthiness Limitations (AWLs) Nos. 28-
AWL-83, 28-AWL-120, 28-AWL-121, 28-AWL-123, 28-AWL-124, and 28-AWL-
125, as applicable, in Section D, ``Summary List of AWLs,'' of
Boeing 787 Special Compliance Items/Airworthiness Limitations,
D011Z009-03-04, dated August 2018, is an acceptable repair.
(i) 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 (j)(1) of this AD. Information may be emailed to:
<a href="/cdn-cgi/l/email-protection#6d2c20222e2d0b0c0c430a021b"><span class="__cf_email__" data-cfemail="73323e3c30331512125d141c05">[email protected]</span></a>. 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.
(j) Additional Information
(1) For more information about this AD, contact Tak Kobayashi,
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA
98198; phone: 206-231-3553; email: <a href="/cdn-cgi/l/email-protection#0a7e6b616b6263796b246165686b736b7962634a6c6b6b246d657c"><span class="__cf_email__" data-cfemail="8afeebe1ebe2e3f9eba4e1e5e8ebf3ebf9e2e3caecebeba4ede5fc">[email protected]</span></a>.
(2) Material identified in this AD that is not incorporated by
reference is available at the address specified in paragraph (k)(3)
of this AD.
(k) 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 B787-81205-SB570053-00
RB, Issue 001, dated November 5, 2025.
(ii) Section D, ``Summary List of AWLs,'' of Boeing 787 Special
Compliance Items/Airworthiness Limitations, D011Z009-03-04, dated
August 2018.
(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 <a href="http://myboeingfleet.com">myboeingfleet.com</a>.
(4) 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.
(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 <a href="http://www.archives.gov/federal-register/cfr/ibr-locations">www.archives.gov/federal-register/cfr/ibr-locations</a> or email <a href="/cdn-cgi/l/email-protection#274155094e4954574244534e4849674946554609404851"><span class="__cf_email__" data-cfemail="ccaabee2a5a2bfbca9afb8a5a3a28ca2adbeade2aba3ba">[email protected]</span></a>.
Issued on October 26, 2026.
Brian Knaup,
Acting Deputy Director, Integrated Certificate Management Division,
Aircraft Certification Service.
[FR Doc. 2026-22318 Filed 10-30-26; 8:45 am]
BILLING CODE 4910-13-P
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