[Federal Register Volume 90, Number 155 (Thursday, August 14, 2025)]
[Rules and Regulations]
[Pages 39093-39102]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-15479]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0339; Project Identifier MCAI-2024-00450-T; 
Amendment 39-23101; AD 2025-16-03]
RIN 2120-AA64


Airworthiness Directives; BAE Systems (Operations) Limited 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2023-02-
06, which applied to all BAE Systems (Operations) Limited Model 4101 
airplanes. AD 2023-02-06 required revising the existing maintenance or 
inspection program, as applicable, to incorporate new or more 
restrictive airworthiness limitations. Since the FAA issued AD 2023-02-
06, new or more restrictive airworthiness limitations have been 
developed. This AD continues to require certain actions in AD 2023-02-
06 and requires revising the existing maintenance or inspection 
program, as applicable to incorporate new or more restrictive 
airworthiness limitations. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective September 18, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of September 
18, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of certain other publications listed in this AD as of March 
14, 2023 (88 FR 7851, February 7, 2023).

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2025-0339; 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, the mandatory continuing airworthiness 
information (MCAI), 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 BAE Systems (Operations) Limited material identified 
in this AD, contact BAE Systems (Operations) Limited, Customer 
Information Department, Prestwick International Airport, Ayrshire, KA9 
2RW, Scotland, United Kingdom; telephone +44 1292 675207; fax +44 1292 
675704; email [email protected]; website baesystems.com/en/our-company/our-businesses/regional-aircraft/about-us.
     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-2025-0339.

FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
phone: 516-228-7300; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2023-02-06, Amendment 39-22313 (88 FR 7851, 
February 7, 2023) (AD 2023-02-06). AD 2023-02-06 applied to all BAE 
Systems (Operations) Limited Model 4101 airplanes. AD 2023-02-06 
required revising the existing maintenance or inspection program, as 
applicable, to incorporate new or more restrictive airworthiness 
limitations. The FAA issued AD 2023-02-06 to address fatigue damage of 
various airplane structures and failure of certain structurally 
significant items, which could result in reduced structural integrity 
of the airplane. The FAA also issued AD 2023-02-06 to address fuel 
vapor ignition sources, which could result in a fuel tank explosion and 
consequent loss of the airplane.
    The NPRM was published in the Federal Register on March 25, 2025 
(90 FR 13561). The NPRM was prompted by AD G-2024-0003, dated August 6, 
2024; corrected August 14, 2024, issued by the Civil Aviation Authority 
(CAA), which is the aviation authority for the United Kingdom (UK) (UK 
CAA AD G-2024-0003) (also referred to as the MCAI). The MCAI states new 
or more restrictive airworthiness limitations have been developed.
    In the NPRM, the FAA proposed to continue to require certain 
actions in AD 2023-02-06. In the NPRM, the FAA also proposed to require 
revising the existing maintenance or inspection program, as applicable, 
to incorporate new or more restrictive airworthiness limitations. The 
FAA is issuing this AD to address fatigue damage of various airplane 
structures and failure of certain structurally significant items, which 
could result in reduced structural integrity of the airplane. The FAA 
is also issuing this AD to address fuel vapor ignition sources, which 
could result in a fuel tank explosion and consequent loss of airplane.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2025-0339.

Discussion of Final Airworthiness Directive Comments

    The FAA received no comments on the NPRM or on the determination of 
the cost to the public.

Conclusion

    These products have been approved by the civil aviation authority 
of another country and are approved for operation in the United States. 
Pursuant to the FAA's bilateral agreement with this State of Design 
Authority, that authority has notified the FAA of the unsafe condition 
described in the MCAI referenced above. 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 Subject 05-10-10, ``Airworthiness Limitations,'' 
of Chapter 05, ``Airworthiness Limitations,'' of BAE Systems 
(Operations) Limited J41 Aircraft Maintenance Manual (AMM), Revision 
46, dated February 20, 2024. This material specifies procedures for 
airworthiness limitations for life-limited parts and structurally 
significant items.
    This AD also requires Chapter 05, ``Airworthiness Limitations,'' of 
BAE Systems (Operations) Limited J41 Aircraft Maintenance Manual (AMM), 
Effectivity Group 403, Revision 44, dated June 15, 2021; and Chapter 
05, ``Airworthiness Limitations,'' of BAE Systems (Operations) Limited 
J41 AMM,

[[Page 39094]]

Effectivity Group 408, Revision 44, dated June 15, 2021; which the 
Director of the Federal Register approved for incorporation by 
reference as of March 14, 2023 (88 FR 7851, February 7, 2023). 
``Effectivity Group'' is not specifically stated on these documents. 
However, ``403'' and ``408,'' which are stated on the pages of the 
applicable documents (except for the title pages), refer to the 
effective groups of airplanes specified within the fleet code listings.
    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.

Other Related Material

    The FAA also reviewed Subject 05-10-20, ``Certification Maintenance 
Requirements,'' of Chapter 05, ``Airworthiness Limitations,'' and 
Subject 05-10-30, ``Critical Design Configuration Control Limitations 
(CDCCL)--Fuel System,'' of Chapter 05, ``Airworthiness Limitations,'' 
of BAE Systems (Operations) Limited J41 Aircraft Maintenance Manual 
(AMM), Revision 45, dated December 15, 2023. This material specifies 
airworthiness limitations for certification maintenance requirements 
and fuel tank systems, which are specified in appendices A and B of 
this AD.

Costs of Compliance

    The FAA estimates that this AD affects 4 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:
    The FAA estimates the total cost per operator for the retained 
actions from AD 2023-02-06 to be $7,650 (90 work-hours x $85 per work-
hour).
    The FAA has determined that revising the 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 x $85 per work-hour).

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:
0
a. Removing Airworthiness Directive (AD) 2023-02-06, Amendment 39-22313 
(88 FR 7851, February 7, 2023); and
0
b. Adding the following new AD:

2025-16-03 BAE Systems (Operations) Limited: Amendment 39-23101; 
Docket No. FAA-2025-0339; Project Identifier MCAI-2024-00450-T.

(a) Effective Date

    This airworthiness directive (AD) is effective September 18, 
2025.

(b) Affected ADs

    This AD replaces AD 2023-02-06, Amendment 39-22313 (88 FR 7851, 
February 7, 2023) (AD 2023-02-06).

(c) Applicability

    This AD applies to all BAE Systems (Operations) Limited Model 
4101 airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 05, Time Limits/
Maintenance Checks.

(e) Unsafe Condition

    This AD was prompted by a determination that new or more 
restrictive airworthiness limitations are necessary. The FAA is 
issuing this AD to address fatigue damage of various airplane 
structures and failure of certain structurally significant items, 
which could result in reduced structural integrity of the airplane. 
The FAA is also issuing this AD to address fuel vapor ignition 
sources, which could result in a fuel tank explosion and consequent 
loss of the airplane.

(f) Compliance

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

(g) Retained Revision of the Existing Maintenance or Inspection 
Program, With a Terminating Action

    This paragraph restates the requirements of paragraph (m) of AD 
2023-02-06, with a new terminating action. Within 90 days after 
March 14, 2023 (the effective date of AD 2023-02-06): Revise the 
existing maintenance or inspection program, as applicable, by 
incorporating Subjects 05-10-10, ``Airworthiness Limitations''; 05-
10-20, ``Certification Maintenance Requirements''; and 05-10-30, 
``Critical Design Configuration Control Limitations (CDCCL)--Fuel 
System''; of Chapter 05, ``Airworthiness Limitations,'' of the BAE 
Systems (Operations) Limited J41 Aircraft Maintenance Manual (AMM), 
Effectivity Group 403, Revision 44, dated June 15, 2021; or BAE 
Systems (Operations) Limited J41 AMM, Effectivity Group 408, 
Revision 44, dated June 15, 2021; as applicable. The initial 
compliance times for the tasks are at the applicable times specified 
in paragraphs (g)(1) through (3) of this AD. Accomplishing the 
revision of the existing maintenance or inspection program required 
by paragraph (i) of this AD terminates the requirements of this 
paragraph.
    (1) For replacement tasks of life limited parts specified in 
Subject 05-10-10, ``Airworthiness Limitations,'' of Chapter 05, 
``Airworthiness Limitations,'' of the BAE Systems (Operations) 
Limited J41 AMM, Effectivity Group 403, Revision 44, dated June 15, 
2021; or BAE Systems (Operations) Limited J41 AMM, Effectivity Group 
408, Revision 44, dated June 15, 2021; as applicable: Prior to the 
applicable flight cycles (landings) or flight hours (flying hours) 
on the part specified in the

[[Page 39095]]

``Mandatory Life Limits'' column in Subject 05-10-10, or within 90 
days after March 14, 2023, whichever occurs later.
    (2) For structurally significant item tasks specified in Subject 
05-10-10, ``Airworthiness Limitations,'' of Chapter 05, 
``Airworthiness Limitations,'' of the BAE Systems (Operations) 
Limited J41 AMM, Effectivity Group 403, Revision 44, dated June 15, 
2021; or BAE Systems (Operations) Limited J41 AMM, Effectivity Group 
408, Revision 44, dated June 15, 2021; as applicable: Prior to the 
accumulation of the applicable flight cycles specified in the 
``Initial Inspection'' column in Subject 05-10-10, or within 90 days 
after March 14, 2023, whichever occurs later.
    (3) For certification maintenance requirements tasks specified 
in Subject 05-10-20, ``Certification Maintenance Requirements,'' of 
Chapter 05, ``Airworthiness Limitations,'' of the BAE Systems 
(Operations) Limited J41 AMM, Effectivity Group 403, Revision 44, 
dated June 15, 2021; or BAE Systems (Operations) Limited J41 AMM, 
Effectivity Group 408, Revision 44, dated June 15, 2021; as 
applicable: Prior to the accumulation of the applicable flight hours 
specified in the ``Time Between Checks'' column in Subject 05-10-20, 
or within 90 days after March 14, 2023, whichever occurs later; 
except for tasks that specify ``first flight of the day'' in the 
``Time Between Checks'' column in Subject 05-10-20, the initial 
compliance time is the first flight of the next day after 
accomplishing the revision required by paragraph (g) of this AD, or 
within 90 days after March 14, 2023, whichever occurs later.

(h) Retained No Alternative Actions, Intervals, or CDCCLs, With New 
Exception

    This paragraph restates the requirements of paragraph (n) of AD 
2023-02-06, with a new exception. Except as required by paragraph 
(i) of this AD: After the existing maintenance or inspection program 
has been revised as required by paragraph (g) of this AD, no 
alternative actions (e.g., inspections), intervals, or CDCCLs may be 
used unless the actions, intervals, and CDCCLs are approved as an 
AMOC in accordance with the procedures specified in paragraph (k)(1) 
of this AD.

(i) New Revision of the Existing Maintenance or Inspection Program

    Within 90 days after the effective date of this AD, revise the 
existing maintenance or inspection program, as applicable, as 
specified in paragraphs (i)(1) and (2) of this AD. Accomplishing the 
revision of the existing maintenance or inspection program required 
by this paragraph terminates the actions required by paragraph (g) 
of this AD.
    (1) Revise the existing maintenance or inspection program, as 
applicable, to incorporate the information specified in Subject 05-
10-10, ``Airworthiness Limitations,'' of Chapter 05, ``Airworthiness 
Limitations,'' of BAE Systems (Operations) Limited J41 AMM, Revision 
46, dated February 20, 2024. The initial compliance time for doing 
the tasks is at the applicable times specified in paragraphs 
(i)(1)(i) and (ii) of this AD.
    (i) For replacement tasks of life limited parts specified in 
Subject 05-10-10, ``Airworthiness Limitations,'' of Chapter 05, 
``Airworthiness Limitations,'' of BAE Systems (Operations) Limited 
J41 AMM, Revision 46, dated February 20, 2024: Prior to the 
applicable flight cycles (landings) or flight hours (flying hours) 
on the part specified in the ``Mandatory Life Limits'' column in 
Subject 05-10-10, or within 90 days after the effective date of this 
AD, whichever occurs later.
    (ii) For structurally significant item tasks specified in 
Subject 05-10-10, ``Airworthiness Limitations,'' of Chapter 05, 
``Airworthiness Limitations,'' of BAE Systems (Operations) Limited 
J41 AMM, Revision 46, dated February 20, 2024: Prior to the 
accumulation of the applicable flight cycles (flights) or years 
specified in the ``Initial Inspection'' column in Subject 05-10-10, 
or within 90 days after the effective date of this AD, whichever 
occurs later.
    (2) Revise the existing maintenance or inspection program, as 
applicable, to incorporate the information in appendix A to this 
AD--Subject 05-10-20, ``Certification Maintenance Requirements,'' 
and in appendix B to this AD--Subject 05-10-30, ``Critical Design 
Configuration Control Limitations (CDCCL)--Fuel System.'' The 
initial compliance time for doing the certification maintenance 
requirements tasks specified in Subject 05-10-20, ``Certification 
Maintenance Requirements'' (appendix A) is prior to the accumulation 
of the applicable flight hours specified in the ``Time Between 
Checks'' column in Subject 05-10-20, or within 90 days after the 
effective date of this AD, whichever occurs later; except for tasks 
that specify ``first flight of the day'' in the ``Time Between 
Checks'' column in Subject 05-10-20, the initial compliance time is 
the first flight of the next day after accomplishing the revision 
required by paragraph (i) of this AD, or within 90 days after the 
effective date of this AD, whichever occurs later.

(j) New No Alternative Actions, Intervals, or CDCCLs

    After the existing maintenance or inspection program has been 
revised as required by paragraph (i) of this AD, no alternative 
actions (e.g., inspections), intervals, or CDCCLs may be used unless 
the actions, intervals, and CDCCLs are approved as an alternative 
method of compliance (AMOC) in accordance with the procedures 
specified in paragraph (k)(1) of this AD.

(k) Additional AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Validation 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 
International Validation Branch, send it to the attention of the 
person identified in paragraph (l) of this AD and email 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) Contacting the Manufacturer: For any requirement in this AD 
to obtain instructions from a manufacturer, the instructions must be 
accomplished using a method approved by the Manager, International 
Validation Branch, FAA; or the UK CAA; or BAE Systems (Operations) 
Limited's UK CAA Design Organization Approval (DOA). If approved by 
the DOA, the approval must include the DOA-authorized signature.

(l) Additional Information

    For more information about this AD, contact Steven Dzierzynski, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: 516-228-7300; email: [email protected].

(m) 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 September 18, 
2025.
    (i) Subject 05-10-10, ``Airworthiness Limitations,'' of Chapter 
05, ``Airworthiness Limitations,'' of BAE Systems (Operations) 
Limited J41 Aircraft Maintenance Manual (AMM), Revision 46, dated 
February 20, 2024.
    (ii) [Reserved]
    (4) The following material was approved for IBR on March 14, 
2023 (88 FR 7851, February 7, 2023).
    (i) Chapter 05, ``Airworthiness Limitations,'' of BAE Systems 
(Operations) Limited J41 AMM, Effectivity Group 403, Revision 44, 
dated June 15, 2021.
    Note 1 to paragraph (m)(4)(i): This note applies to paragraphs 
(m)(4)(i) and (ii) of this AD. Page 1 of the ``Publications 
Transmittal'' is the only page that shows the revision level of this 
document.
    Note 2 to paragraph (m)(4)(i): This note applies to paragraphs 
(m)(4)(i) and (ii) of this AD. ``Effectivity Group'' is not 
specifically stated on the document. However, ``403'' and ``408,'' 
which are stated on the pages of the applicable documents (except 
for the title pages), refer to the effective groups of airplanes 
specified within the fleet code listings.
    (ii) Chapter 05, ``Airworthiness Limitations,'' of BAE Systems 
(Operations) Limited J41 AMM, Effectivity Group 408, Revision 44, 
dated June 15, 2021.
    (5) For BAE Systems (Operations) Limited material identified in 
this AD, contact BAE Systems (Operations) Limited, Customer 
Information Department, Prestwick International Airport, Ayrshire, 
KA9 2RW, Scotland, United Kingdom; telephone +44 1292 675207; fax 
+44 1292 675704; email [email protected]; website 
baesystems.com/en/our-company/our-businesses/regional-aircraft/about-us.
    (6) You may view this material at the FAA, Airworthiness 
Products Section, Operational

[[Page 39096]]

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 [email protected].
BILLING CODE 4910-13-P

Appendix A to AD 2025-16-03--Subject 05-10-20, ``Certification 
Maintenance Requirements''
[GRAPHIC] [TIFF OMITTED] TR14AU25.000


[[Page 39097]]


[GRAPHIC] [TIFF OMITTED] TR14AU25.001


[[Page 39098]]


[GRAPHIC] [TIFF OMITTED] TR14AU25.002


[[Page 39099]]


[GRAPHIC] [TIFF OMITTED] TR14AU25.003


[[Page 39100]]


[GRAPHIC] [TIFF OMITTED] TR14AU25.004

    Source: Chapter 05, ``Airworthiness Limitations,'' of the BAE 
Systems (Operations) Limited J41 AMM.

[[Page 39101]]

Appendix B to AD 2025-16-03--Subject 05-10-30, ``Critical Design 
Configuration Control Limitations (CDCCL)--Fuel System''
[GRAPHIC] [TIFF OMITTED] TR14AU25.005


[[Page 39102]]


[GRAPHIC] [TIFF OMITTED] TR14AU25.006

    Source: Chapter 05, ``Airworthiness Limitations,'' of the BAE 
Systems (Operations) Limited J41 AMM.

    Issued on August 4, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-15479 Filed 8-13-25; 8:45 am]
BILLING CODE 4910-13-C