[Federal Register Volume 90, Number 225 (Tuesday, November 25, 2025)]
[Proposed Rules]
[Pages 53243-53245]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-21100]
[[Page 53243]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2025-3439; Project Identifier AD-2025-00463-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 certain The Boeing Company Model 737-8, 737-9, and 737-8200 (737
MAX) airplanes. This proposed AD was prompted by reports indicating
cracks in the bear strap and stub frame at the forward galley door
cutout. This proposed AD would require inspections for existing
repairs; an inspection for any crack of the fuselage skin, bear strap,
and stub frame; repetitive inspections for any crack of the bear strap
and stub frame; 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 January 9,
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-2025-3439; 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-2025-3439.
FOR FURTHER INFORMATION CONTACT: Luis Cortez-Muniz, Aviation Safety
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-
231-3958; email: [email protected].
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-2025-3439;
Project Identifier AD-2025-00463-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 Luis
Cortez-Muniz, Aviation Safety Engineer, FAA, 2200 South 216th St., Des
Moines, WA 98198; phone: 206-231-3958; email: [email protected]. 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 reports indicating that cracking was found in
the bear strap and stub frame at the forward galley door cutout, from
station (STA) 290 to STA 296 and between stringer S-8R and stringer S-
9R, on certain Model 737-600, -700, -700C, -800, -900, and -900ER
series airplanes (737NG airplanes). Boeing investigated and found
surface scratches on the bear strap, which were inadvertently created
while removing sealant and adhesive during hot bonding process of
fuselage skin and bear strap. The presence of these scratches, along
with local elevated stresses in the bear strap, cause a reduction in
fatigue life and early cracking. Although no cracks have been reported
in the same areas on The Boeing Company Model 737 MAX airplanes, The
Boeing Company Model 737 MAX airplanes have similar design and build
process, making The Boeing Company Model 737 MAX airplanes susceptible
to the same crack condition. This condition, if not addressed, may
result in the inability of a principal structural element to sustain
limit load, which could adversely affect the structural integrity of
the airplane.
Boeing issued Requirements Bulletin 737-53A1383 to address the
identified unsafe condition for The Boeing Company Model 737NG
airplanes. Subsequently, the FAA issued AD 2021-02-13, Amendment 39-
21396 (86 FR10776, February 23, 2021) to require inspections of the
fuselage skin and bear strap at the forward galley door between certain
stations for cracks, and applicable on-condition actions, in accordance
with Boeing Alert Requirements Bulletin 737-53A1383 RB, Revision 1,
dated February 19, 2020.
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 737-53A1420 RB,
dated February 13, 2025. This material specifies procedures for doing
[[Page 53244]]
Option 1 or Option 2 actions as specified below, and applicable on-
condition actions. On-condition actions include replacing the stub
frame, doing alternative inspections, and doing a repair.
Option 1--Perform initial external general visual
inspection (GVI) of the fuselage skin and gap cover for any repair,
initial internal GVI of the bear strap and stub frame for any repair,
and repetitive internal high frequency eddy current (HFEC) inspections
of the bear strap and stub frame for any crack.
Option 2--Perform initial external GVI of the fuselage
skin and gap cover for any repair, initial internal GVI of the stub
frame for any repair, initial external HFEC inspection of the fuselage
skin for any crack, initial external low frequency eddy current (LFEC)
inspection of the bear strap for any crack, initial internal HFEC
inspection of the stub frame for any crack, and repetitive internal
HFEC inspections of the bear strap and stub frame for any crack.
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-2025-3439.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 476 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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Option 1--Initial inspections.... 31 work-hours x $85 $0 $2,635............. $1,254,260.
per hour = $2,635.
Option 2--Initial inspections.... 7 work-hours x $85 0 $595............... $283,220.
per hour = $595.
Repetitive internal HFEC 29 work-hours x $85 0 $2,465 per $1,173,340 per
inspections of the bear strap per hour = $2,465 inspection cycle. inspection cycle.
and stub frame per Option 1 or per inspection
Option 2. cycle.
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The FAA estimates the following costs to do any necessary
replacements that would be required based on the results of the
proposed inspection. The agency has no way of determining the number of
aircraft that might need this replacement:
On-Condition Costs
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Cost per
Action Labor cost Parts cost product
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Replace the stub frame....................... 35 work-hours x $85 per hour = $1,359 $4,334
$2,975.
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The FAA has received no definitive data that would enable the
agency to provide cost estimates for the on-condition repairs 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.
[[Page 53245]]
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-2025-3439; Project Identifier AD-
2025-00463-T.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive
(AD) by January 9, 2026.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 737-8, 737-9, and
737-8200 airplanes, certificated in any category, as identified in
Boeing Alert Requirements Bulletin 737-53A1420 RB, dated February
13, 2025.
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by reports indicating cracks in the bear
strap and stub frame at the forward galley door cutout, from station
(STA) 290 to STA 296 and between stringer S-8R and stringer S-9R.
The FAA is issuing this AD to address any crack in the fuselage
skin, bear strap, and stub frame at the forward galley door cutout
from STA 290 to STA 296 and between stringer S-8R and stringer S-9R,
before it reaches critical length. The unsafe condition, if not
addressed, may result in the inability of a principal structural
element to sustain limit load, which could adversely affect the
structural integrity of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
Except as specified in paragraph (h) of this AD: At the
applicable times specified in the ``Compliance'' paragraph of Boeing
Alert Requirements Bulletin 737-53A1420 RB, dated February 13, 2025,
do all applicable actions identified in, and in accordance with, the
Accomplishment Instructions of Boeing Alert Requirements Bulletin
737-53A1420 RB, dated February 13, 2025.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
737-53A1420, dated February 13, 2025, which is referred to in Boeing
Alert Requirements Bulletin 737-53A1420 RB, dated February 13, 2025.
(h) Exceptions to Requirements Bulletin Specifications
(1) Where the Compliance Time columns of the tables in the
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 737-
53A1420 RB, dated February 13, 2025, refers to the original issue
date of Requirements Bulletin 737-53A1420 RB, this AD requires using
the effective date of this AD.
(2) Where Boeing Alert Requirements Bulletin 737-53A1420 RB,
dated February 13, 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:
[email protected]. 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) Related Information
For more information about this AD, contact Luis Cortez-Muniz,
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA
98198; phone: 206-231-3958; email: [email protected].
(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 737-53A1420 RB, dated
February 13, 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 myboeingfleet.com.
(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 www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].
Issued on October 20, 2025.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft
Certification Service.
[FR Doc. 2025-21100 Filed 11-24-25; 8:45 am]
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