[Federal Register Volume 91, Number 44 (Friday, March 6, 2026)]
[Rules and Regulations]
[Pages 10956-10959]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2026-04466]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0741; Project Identifier AD-2025-00153-T; 
Amendment 39-23270; AD 2026-04-10]
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 767-200, 767-300, 767-300F, and 767-
400ER airplanes. This AD was prompted by a heavy maintenance check that 
found corrosion damage on a Model 767 satellite communications (SATCOM) 
high gain antenna adapter plate. This AD requires repetitive detailed 
inspections (DET) of the SATCOM high gain antenna adapter plate for 
corrosion and applicable on-condition actions. The FAA is issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective April 10, 2026.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of April 10, 
2026.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2025-0741; 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:
     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.
     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-2025-0741.

FOR FURTHER INFORMATION CONTACT: Stefanie Roesli, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-
231-3964; email: [email protected].

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 767-200, 767-300, 767-300F, and 767-400ER airplanes. The 
NPRM was published in the Federal Register on April 29, 2025 (90 FR 
17741). The NPRM was prompted by a heavy maintenance check that found 
corrosion damage on a Model 767 SATCOM high gain antenna adapter plate. 
In the NPRM, the FAA proposed to require repetitive DET of the SATCOM 
high gain antenna adapter plate for corrosion and applicable on 
condition actions. The FAA is issuing this AD to prevent corrosion 
damage of the SATCOM high gain antenna adapter plates, which could 
result in parts departing the airplane (PDA). A PDA event of the SATCOM 
high gain antenna system could damage the primary flight control 
surfaces which may result in loss of continued safe flight and landing 
of the airplane.

[[Page 10957]]

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from Air Line Pilots Association, 
International (ALPA), Boeing, and United Airlines, who supported the 
NPRM without change.
    In addition, the FAA received a comment from Delta Air Lines, Inc. 
(Delta). The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Request To Differentiate Between a Repaired Adapter Plate and an 
Adapter Plate With No Damage

    Delta requested that the FAA revise paragraph (h) of the proposed 
AD to differentiate between a serviceable SATCOM adapter plate that has 
been inspected for corrosion with no damage findings and a repaired 
SATCOM adapter plate that has been inspected for corrosion and 
applicable on-condition corrective actions have been done. Delta also 
requested that the FAA add these specifications to the applicable table 
conditions and increase the repeat inspection interval for serviceable 
adapter plates to 96 months. Delta stated that the wording in note (b) 
of Boeing Alert Requirements Bulletin 767-23A0351 RB, dated January 23, 
2025, does not differentiate between an adapter plate that may have 
been repaired and one that has been inspected with no damage found and 
suggested that an adapter plate with no damage should be treated the 
same as a new adapter plate, with the repeat inspection interval for 
serviceable adapter plates increased to 96 months to match that of a 
new adapter plate.
    The FAA does not agree with the request. The definition for a 
serviceable SATCOM adapter plate in note (b) of Boeing Alert 
Requirements Bulletin 767-23A0351 RB, dated January 23, 2025, addresses 
both scenarios specified in Delta's comment. An adapter plate that has 
been inspected for corrosion, with applicable on-condition corrective 
actions performed, may have been repaired, and one that has been 
inspected with no damage found is included as part of the ``applicable 
on-condition corrective actions'' statement in Boeing Alert 
Requirements Bulletin 767-23A0351 RB, dated January 23, 2025. The FAA 
has not changed this AD in this regard.

Request To Verify Aircraft Maintenance Manual (AMM)

    Delta requested that the FAA provide guidance on AMM 23-25-18 and 
AMM 53-66-11, which are specified in Boeing Alert Service Bulletin 767-
23A0351, dated January 23, 2025. Delta suggested that there might be an 
error in the AMM numbers, since they are not located within the 
original equipment manufacturer (OEM) AMM manual. Delta stated that it 
does not have Boeing 767 AMM 23-25-18 and AMM 53-66-11 for antenna and 
adapter plate remove/installation and therefore cannot determine if AMM 
23-25-19 for antenna and adapter plate install/removal is comparable to 
AMM 23-25-18 and AMM 53-66-11.
    The FAA does not agree with the request. The FAA notes that the 
work instructions specified are in Boeing Alert Service Bulletin 767-
23A0351, dated January 23, 2025, not the mandated Boeing Alert 
Requirements Bulletin 767-23A00351 RB, dated January 23, 2025, and are 
therefore outside the scope of this AD. In addition to containing the 
same information that is required for compliance with the requirements 
bulletin, the service bulletin provides additional guidance, including 
references to accepted procedures for accomplishing the required 
actions. Since the references to the AMM sections in the service 
bulletin are ``referred to'' as additional guidance, operators are not 
required to use these sections to accomplish the removal, repair or 
replacement, and installation of the SATCOM high gain antenna adapter 
plate. Operators may use the appropriate AMM sections to accomplish the 
required actions. The FAA has not changed this AD in this regard.

Request for Corrosion Inhibiting Compounds (CIC) Application

    Delta requested the FAA add an exception to paragraph (h) of the 
proposed AD to allow the application of BMS3-26, BMS3-29, or equivalent 
CIC to the adapter plate and increase the inspection intervals 
accordingly. Delta noted that although this is a corrosion-related 
issue, Boeing Alert Requirements Bulletin 767-23A0351 RB, dated January 
23, 2025, does not recommend CIC application for corrosion. Delta 
suggested that CIC application would improve the corrosion protection 
of the plate and could therefore add time to the inspection intervals.
    The FAA does not agree with the request. Substantiation would be 
necessary to justify the use of CIC and an increase of the repeat 
inspection interval. However, under the provisions of paragraph (i) of 
this AD, the FAA will consider requests for approval of an alternative 
method of compliance (AMOC) if sufficient data are submitted to 
substantiate an acceptable level of safety. The FAA has not changed 
this AD in this regard.

Additional Changes to This Final Rule

    In the NPRM, the FAA inadvertently omitted the ``Effectivity'' 
paragraph and the ``Condition'' paragraph from the exception in 
paragraph (h), Exceptions to Requirements Bulletin Specifications, of 
the proposed AD. The FAA has revised paragraph (h) of this AD to 
include these paragraphs in that exception.

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, 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 767-23A0351 RB, 
dated January 23, 2025. This material specifies procedures for 
repetitive DET of the SATCOM high gain antenna adapter plate for 
corrosion and applicable on-condition actions. On-condition actions 
include repairing the SATCOM high gain antenna adapter plate or 
replacing it with a new or serviceable SATCOM high gain antenna adapter 
plate if any corrosion found is less than or equal to 0.005 inch in 
depth; and replacing the SATCOM high gain antenna adapter plate with a 
new or serviceable SATCOM high gain antenna adapter plate if any 
corrosion found is greater than 0.005 inch in depth.
    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 597 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

[[Page 10958]]



                                                 Estimated Costs
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                                                                                                Cost on U.S.
              Action                    Labor cost        Parts cost    Cost per product          operators
----------------------------------------------------------------------------------------------------------------
Detailed inspection..............  11 work-hours x $85            $0  $935 per inspection   $558,195 per
                                    per hour = $935 per                cycle.                inspection cycle.
                                    inspection cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any repair or 
replacement that would be required based on the results of the 
inspection. The agency has no way of determining the number of 
airplanes that might need this repair or replacement:

                                               On-Condition Costs
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                    Action                                Labor cost              Parts cost   Cost per product
----------------------------------------------------------------------------------------------------------------
Repair adapter plate.........................  5 work-hours x $85 per hour =              $0                $425
                                                $425.
Replace adapter plate........................  2 work-hours x $85 per hour =          18,000              18,170
                                                $170.
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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:

2026-04-10 The Boeing Company: Amendment 39-23270; Docket No. FAA-
2025-0741; Project Identifier AD-2025-00153-T.

(a) Effective Date

    This airworthiness directive (AD) is effective April 10, 2026.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 767-200, 767-300, 
767-300F, and 767-400ER airplanes, certificated in any category, as 
identified in Boeing Alert Requirements Bulletin 767-23A0351 RB, 
dated January 23, 2025.

(d) Subject

    Air Transport Association (ATA) of America Code 23, 
Communications.

(e) Unsafe Condition

    This AD was prompted by a heavy maintenance check that found 
corrosion damage on a Model 767 satellite communications (SATCOM) 
high gain antenna adapter plate. The FAA is issuing this AD to 
prevent corrosion damage of the SATCOM high gain antenna adapter 
plates, which could result in parts departing the airplane (PDA). A 
PDA event of the SATCOM high gain antenna system could damage the 
primary flight control surfaces which may result in loss of 
continued safe flight and landing of the airplane.

(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 767-23A0351 RB, dated January 23, 2025, 
do all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions Boeing Alert Requirements Bulletin 767-
23A0351 RB, dated January 23, 2025.
    Note 1 to paragraph (g): Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
767-23A0351, dated January 23, 2025, which is referred to in Boeing 
Alert Requirements Bulletin 767-23A0351 RB, dated January 23, 2025.

(h) Exceptions to Requirements Bulletin Specifications

    Where the ``Effectivity'' paragraph and the Condition and Boeing 
Recommended Compliance Time columns of the tables in the 
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 767-
23A0351 RB, dated January 23, 2025, refer to the original issue date 
of Requirements Bulletin 767-23A0351 RB, this AD requires using the 
effective date 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 certification office,

[[Page 10959]]

send it to the attention of the person identified in paragraph 
(j)(1) of this AD. Information may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the responsible Flight Standards Office.
    (3) 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 Stefanie Roesli, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; phone: 206-231-3964; email: [email protected].
    (2) Material identified in this AD that is not incorporated by 
reference is available at the address specified in paragraph (k)(3) 
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 767-23A0351 RB, dated 
January 23, 2025.
    (ii) [Reserved]
    (3) For the 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 February 19, 2026.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2026-04466 Filed 3-5-26; 8:45 am]
BILLING CODE 4910-13-P