Proposed Rule2026-06385
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
April 2, 2026
Issuing agencies
Transportation DepartmentFederal Aviation Administration
Abstract
The FAA proposes to adopt a new airworthiness directive (AD) for all The Boeing Company Model 757-300 series airplanes. This proposed AD was prompted by a crack growth analysis that indicated that existing maintenance planning data (MPD) and supplemental structural inspection program (SSIP) tasks do not provide adequate inspection opportunities to detect cracks in the upper frames around the uppermost fastener common to the fail-safe chord at the fuselage frame splices. This proposed AD would require an inspection or maintenance record check for existing repairs, repetitive inspections of the upper frames around the uppermost fastener common to the fail-safe chord at the fuselage frame splices for any cracks, and applicable on-condition actions. The FAA is proposing this AD to address the unsafe condition on these products.
Full Text
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<title>Federal Register, Volume 91 Issue 63 (Thursday, April 2, 2026)</title>
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[Federal Register Volume 91, Number 63 (Thursday, April 2, 2026)]
[Proposed Rules]
[Pages 16593-16595]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-06385]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2026-2730; Project Identifier AD-2025-01579-T]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all The Boeing Company Model 757-300 series airplanes. This
proposed AD was prompted by a crack growth analysis that indicated that
existing maintenance planning data (MPD) and supplemental structural
inspection program (SSIP) tasks do not provide adequate inspection
opportunities to detect cracks in the upper frames around the uppermost
fastener common to the fail-safe chord at the fuselage frame splices.
This proposed AD would require an inspection or maintenance record
check for existing repairs, repetitive inspections of the upper frames
around the uppermost fastener common to the fail-safe chord at the
fuselage frame splices for any cracks, and applicable on-condition
actions. 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 18,
2026.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
<bullet> Federal eRulemaking Portal: Go to <a href="http://regulations.gov">regulations.gov</a>. Follow
the instructions for submitting comments.
<bullet> Fax: 202-493-2251.
<bullet> 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.
<bullet> 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 <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-2730; 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:
<bullet> 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 <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-2026-2730.
FOR FURTHER INFORMATION CONTACT: Wayne Ha, Aviation Safety Engineer,
FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5238;
email: <a href="/cdn-cgi/l/email-protection#4730263e2922692f260721262669202831"><span class="__cf_email__" data-cfemail="6f180e16010a41070e2f090e0e41080019">[email protected]</span></a>.
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-2026-2730;
Project Identifier AD-2025-01579-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
<a href="http://regulations.gov">regulations.gov</a>, 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 Wayne
Ha, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA
98198; phone: 562-627-5238; email: <a href="/cdn-cgi/l/email-protection#1c6b7d65727932747d5c7a7d7d327b736a"><span class="__cf_email__" data-cfemail="ed9a8c948388c3858cad8b8c8cc38a829b">[email protected]</span></a>. 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 has received a report that crack growth analysis indicated
that existing MPD and SSIP tasks do not provide adequate inspection
opportunities to detect cracks in the upper frames around the uppermost
fastener common to the fail-safe chord at the fuselage frame splices
between stringers S-13 to S-14, from station (STA) 1380 to STA 1620.
Any undetected crack in the upper frames around the uppermost fastener
common to the S-13 to S-14 frame splices could
[[Page 16594]]
lead to multiple upper frame failures. This condition, if not
addressed, could result in the inability of a principal structural
element to sustain limit loads and the loss of continued safe flight
and landing.
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 757-53A0122 RB,
dated September 26, 2025. This material specifies procedures for
performing a general visual inspection or a maintenance records check
of the forward and aft sides of the upper frames at the frame splices
between S-13 and S-14 on the left and right sides, from STA 1380 to STA
1620, for any repair and applicable on-condition actions. On-condition
actions include contacting Boeing for alternative inspection and
corrective action instructions and doing the alternative inspection and
applicable corrective actions in the repaired areas.
This material also specifies procedures for repetitive detailed
inspections of the upper frames around the uppermost fastener common to
the fail-safe chord at the frame splices between S-13 and S-14 on the
left and right sides, from STA 1380 to STA 1620, for any crack and
applicable on-condition actions. On-condition actions include
contacting Boeing for repair instructions and doing the 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.
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 <a href="http://regulations.gov">regulations.gov</a> under Docket No. FAA-2026-2730.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 37 airplanes of U.S. registry. The FAA estimates the following
costs to comply with this proposed AD:
Estimated Costs
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Cost on U.S.
Action Labor cost Parts cost Cost per product operators
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General visual inspection or Up to 70 work-hours $0 Up to $5,950........ Up to $220,150.
maintenance records check. x $85 per hour =
$5,950.
Detailed inspection.............. 4 work-hours x $85 0 $340 per inspection $12,580 per
per hour = $340 per cycle. inspection cycle.
inspection cycle.
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The FAA has received no definitive data on which to base the cost
estimates for the alternative inspections and on-condition actions
specified in this proposed AD.
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
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:
The Boeing Company: Docket No. FAA-2026-2730; Project Identifier AD-
2025-01579-T.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive
(AD) by May 18, 2026.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 757-300 series
airplanes, certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by a crack growth analysis that indicated
that the existing maintenance planning data and supplemental
structural inspection program tasks do not provide adequate
inspection opportunities to detect cracks in the upper frames around
the uppermost fastener common to the fail-safe chord at certain
fuselage frame splices. The FAA is issuing this AD to address
cracking in the upper frames around the uppermost fastener common to
the fail-safe chord at certain fuselage frame splices, which could
lead to
[[Page 16595]]
multiple upper frame failures. The unsafe condition, if not
addressed, could result in the inability of a principal structural
element to sustain limit loads and the 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 757-53A0122 RB, dated September 26,
2025, do all applicable actions identified in, and in accordance
with, the Accomplishment Instructions of Boeing Alert Requirements
Bulletin 757-53A0122 RB, dated September 26, 2025.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
757-53A0122, dated September 26, 2025, which is referred to in
Boeing Alert Requirements Bulletin 757-53A0122 RB, dated September
26, 2025.
(h) Exceptions to Requirements Bulletin Specifications
(1) Where the Compliance Time column of the tables in the
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 757-
53A0122 RB, dated September 26, 2025, refers to the original issue
date of Requirements Bulletin 757-53A0122 RB, this AD requires using
the effective date of this AD.
(2) Where Boeing Alert Requirements Bulletin 757-53A0122 RB,
dated September 26, 2025, specifies contacting Boeing for repair
instructions or for alternative inspections: This AD requires doing
the repair, or doing the alternative inspections and applicable on-
condition actions, using a method approved in accordance with the
procedures specified in paragraph (i) of this AD.
(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) of this AD. Information may be emailed to:
<a href="/cdn-cgi/l/email-protection#46070b09050620272768212930"><span class="__cf_email__" data-cfemail="b4f5f9fbf7f4d2d5d59ad3dbc2">[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
For more information about this AD, contact Wayne Ha, Aviation
Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198;
phone: 562-627-5238; email: <a href="/cdn-cgi/l/email-protection#c4b3a5bdaaa1eaaca584a2a5a5eaa3abb2"><span class="__cf_email__" data-cfemail="94e3f5edfaf1bafcf5d4f2f5f5baf3fbe2">[email protected]</span></a>.
(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 757-53A0122 RB, dated
September 26, 2025.
(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 <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#0f697d2166617c7f6a6c7b6660614f616e7d6e21686079"><span class="__cf_email__" data-cfemail="5432267a3d3a27243137203d3b3a143a3526357a333b22">[email protected]</span></a>.
Issued on March 27, 2026.
Lona C. Saccomando,
Acting Deputy Director, Integrated Certificate Management Division,
Aircraft Certification Service.
[FR Doc. 2026-06385 Filed 4-1-26; 8:45 am]
BILLING CODE 4910-13-P
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