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[Federal Register Volume 90, Number 22 (Tuesday, February 4, 2025)]
[Rules and Regulations]
[Pages 8870-8874]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-02187]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-1299; Project Identifier MCAI-2023-00237-A; 
Amendment 39-22925; AD 2025-01-01]
RIN 2120-AA64

Airworthiness Directives; Britten-Norman Aerospace Ltd. 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 Britten-Norman Aerospace Ltd. Model BN-2, BN-2A, BN-2A-2, BN-
2A-3, BN-2A-6, BN-2A-8, BN-2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-
27, BN-2B-20, BN-2B-21, BN-2B-26, BN-2B-27, BN-2T, BN2T-4R, and BN2T-4S 
airplanes; and certain Model BN2A MK. III, BN2A MK. III-2, and BN2A MK. 
III-3 airplanes. This AD was prompted by the determination that, in 
order to ensure the continued structural integrity of certain landing 
gear and associated components, it is necessary to require removal of 
these components from service prior to exceeding established fatigue 
lives. This AD

[[Page 8871]]

requires determining the number of landings on affected main landing 
gears (MLGs), nose landing gears (NLGs), and associated components; 
removing from service any part that has reached or exceeded the 
established fatigue life and installing a replacement part; and 
prohibiting the installation of any affected part unless the number of 
landings for that part is below the established fatigue life. The FAA 
is issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective March 11, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 11, 
2025.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No.FAA-2024-1299; 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 Britten-Norman material identified in this AD, contact 
Britten-Norman Aerospace Ltd., Bembridge Airport, Bembridge, Isle of 
Wight, UK, PO35 5PR; phone: +44 20 3371 4000; email: 
norman.com">customer.support@britten-norman.com; website: britten-norman.com/approvals-technical-publications.
     You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 901 Locust, Kansas City, 
MO 64106. For information on the availability of this material at the 
FAA, call (817) 222-5110. It is also available at regulations.gov under 
Docket No. FAA-2024-1299.

FOR FURTHER INFORMATION CONTACT: Beenal Desai, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
phone: (609) 485-9930; 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 Britten-Norman 
Aerospace Ltd. Model BN-2, BN-2A, BN-2A-2, BN-2A-3, BN-2A-6, BN-2A-8, 
BN-2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-27, BN-2B-20, BN-2B-21, 
BN-2B-26, BN-2B-27, BN-2T, BN2T-4R, and BN2T-4S (Islander) airplanes; 
and Model BN2A MK. III, BN2A MK. III-2, and BN2A MK. III-3 (Trislander) 
airplanes, fitted with landing gear and associated components 
manufactured by Fairey Hydraulics Ltd (FHL) and Britten-Norman Aircraft 
(BNA). The NPRM published in the Federal Register on May 17, 2024 (89 
FR 43342). The NPRM was prompted by AD G-2023-0001, dated February 8, 
2023, issued by Civil Aviation Authority (CAA), which is the aviation 
authority for the United Kingdom (UK) (UK CAA AD G-2023-0001) (also 
referred to as the MCAI). The MCAI states that to ensure the continued 
safe operation of certain Islander's and Trislander's NLG, MLG, and 
associated components, the manufacturer and the UK CAA determined that 
affected parts exceeding the established fatigue lives must be removed 
from service and that installation of parts that have reached their 
established fatigue lives must be prohibited.
    In the NPRM, the FAA proposed to require determining the number of 
landings on affected MLGs, NLGs, and associated components; removing 
from service any part that has reached or exceeded the established 
fatigue life and installing a replacement part; and prohibiting the 
installation of any affected part unless the number of landings for 
that part is below the established fatigue life. The FAA is issuing 
this AD to address the unsafe condition on these products. Exceeding 
the established fatigue life, if not addressed, could result in failure 
of the structural integrity of the landing gear and associated 
components, which could result in damage to the airplane and injury to 
occupants.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2024-1299.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from one individual commenter. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Request To Include a Method for Calculating Landings Per Flight Hour

    The commenter stated that in the United States landings are not 
required to be tracked on general aviation or commercial use non turbo 
prop airplanes. The commenter also mentioned that AD 2002-25-03, 
Amendment 39-12978 (67 FR 76106, December 11, 2002) provides a 
calculation of 3 landings per flight hour to calculate the number of 
landings, but this calculation is not realistic for all airplane 
operations and should be re-evaluated. The commenter explained it is 
difficult to take off and land three times in an hour with taxi, 
loading, and unloading of passengers and cargo. The commenter stated 
that if a routine flight was 30 minutes to an hour, then 1 or 2 
landings for 1 flight hour should be considered by the FAA. The FAA 
infers that the commenter is requesting that the NPRM be revised to 
include a method for calculating landings per flight hour.
    The FAA partially agrees with the commenter's request. The FAA 
acknowledges that landings are not required to be tracked on domestic 
general aviation airplanes. The compliance time for this AD is based on 
the number of landings because the affected MLGs, NLGs, and associated 
components that are showing fatigue are used during landing operations.
    The FAA revised paragraph (h)(1) of this AD to specify how to 
calculate for an unknown number of landings and requires using 3 
landings per 1 hour time-in-service (TIS). The FAA disagrees with using 
the calculation of 1 or 2 landings per 1 hour TIS because the 3 
landings per 1 hour TIS calculation is a conservative estimate and has 
been used in previous ADs. The FAA received information from Britten-
Norman that supported using a calculation of 3 landings per 1 hour TIS. 
In addition, Britten-Norman does not have any data to substantiate 
decreasing the number of landings to 1 or 2 landings per 1 hour TIS. 
The FAA disagrees with referring to ``flight hours'' and is referring 
to TIS because ``flight hours'' are not defined in FAA regulations but 
TIS is defined in FAA regulations and is used with respect to 
maintenance records.

Request for Extension of Fatigue Life Landings by 30 Percent

    The commenter requested that the FAA allow a 30-percent increase of 
the fatigue life values specified in Tables 1, 2, and 3 of Section 6 in 
Britten-Norman Service Bulletin SB 298, Issue 3, dated July 7, 2023 
(Britten-Norman SB 298, Issue 3). The commenter stated that other 
countries allow the affected airplanes to operate with heavier gross 
weights than the United States allows, which reduces the fatigue lives 
of the affected components by shortening them. The commenter suggested 
a periodic eddy current inspection to determine the fatigue life value.

[[Page 8872]]

    The FAA disagrees with both the commenter's request for a 30-
percent fatigue life value increase and the commenter's suggestion to 
use a periodic eddy current inspection to determine the fatigue life 
value. The commenter did not provide substantiating data to support the 
requested changes. Britten-Norman provided the fatigue lives for the 
affected MLGs, NLGs, and associated components for the worldwide fleet 
based on its analysis of the unsafe condition and does not have data to 
substantiate increasing the fatigue life by 30-percent. The FAA agrees 
with this determination for airplanes on the U.S. registry. Operators 
may submit a proposal, with substantiating data, for revised 
requirements that affect the fatigue life value by requesting an 
alternative method of compliance (AMOC) using the procedures specified 
in paragraph (j) of this AD.
    The FAA has not changed this AD regarding this comment.

Request for Compliance Time Based on Operating Environments and 
Conditions

    The commenter stated that operating environments and conditions 
should also be considered when establishing compliance times. The 
commenter explained that these are excellent cargo and passenger 
airplanes and are flown all over the world in remote places with short, 
unimproved runways of dirt and gravel. The commenter stated that these 
are extreme operating conditions that most airplanes do not encounter 
and the comparison between airplanes operated in the United States and 
airplanes operated in other countries are not equal.
    The FAA disagrees with the commenter's request to change the 
compliance time based on airplane operating environments and 
conditions. There is no current requirement to track the hours spent 
flying in different conditions. Additionally, operators may not know an 
airplane's entire flight or maintenance history. Without this detailed 
knowledge of each airplane, it would be impossible for the FAA to 
develop a special set of inspections based on airplane operating 
environments and conditions. However, operators may submit a proposal, 
with substantiating data, for revised requirements by requesting an 
AMOC using the procedures specified in paragraph (j) of this AD.
    The FAA has not changed this AD regarding this comment.

Request To Allow Continued Use of Parts That Exceed Fatigue Life Until 
Replacement Parts Are Available

    The commenter requested that the MLG, NLG, and associated 
components that exceed the fatigue lives specified in in Tables 1, 2, 
and 3 of Section 6 in Britten-Norman SB 298, Issue 3, be allowed to 
continue to be used in service until replacement parts are available. 
The commenter referred to paragraph 2, ``Corrective Action,'' of UK CAA 
AD G-2023-0001, which states ``Any main or nose landing gear or 
component which exceed the fatigue life stated in Tables 1, 2 or 3 must 
be withdrawn from service immediately.'' The commenter stated that if 
replacement parts are not available then the proposed AD would not only 
ground the fleet but close businesses that rely on these airplanes.
    The FAA disagrees with allowing parts that exceed the fatigue life 
to be allowed in-service until replacement parts are available. While 
the FAA acknowledges the commenter's concern regarding immediately 
removing parts that exceed the specified fatigue lives from service, 
this AD does not require immediately removing from service affected 
parts that exceed the specified fatigue lives. Paragraph (h)(2) of this 
AD provides a grace period of 30 days after the effective date of this 
AD for replacing affected parts that exceed the specified fatigue 
lives. Britten-Norman has confirmed that the landing gear is still in 
production and spares are available. To the extent replacement parts 
may not be available, the FAA cannot base its AD action on whether 
replacement parts are available or can be produced. While every effort 
is made to avoid grounding airplanes, the FAA must address the unsafe 
condition. Operators may submit a proposal for revised requirements, 
with substantiating data, by requesting an AMOC using the procedures 
specified in paragraph (j) of this AD.
    The FAA has not changed this AD regarding this comment.

Conclusion

    These products have been approved by the 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, it has notified the FAA of the unsafe condition described in 
the MCAI referenced above. The FAA reviewed the relevant data, 
considered the 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 changes described previously, this AD 
is adopted as proposed in the NPRM. None of the changes increase the 
economic burden on any operator.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed Britten-Norman SB 298, Issue 3. This material 
provides procedures for identifying the affected MLGs, NLGs, and 
associated components that need to have the number of landings tracked 
and provides the associated fatigue life. This material also specifies 
to remove from service any affected part that exceeds the specified 
fatigue life.
    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 87 airplanes of U.S. 
registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
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            Action                  Labor cost      Parts cost     Cost per product      Cost on U.S. operators
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Determine the number of         1 work-hour x $85           $0  $85...................  $7,395.
 landings accumulated on         per hour = $85.
 affected MLGs, NLGs, and
 associated components.
Replace MLG...................  16 work-hours x         30,000  31,360................  2,728,320.
                                 $85 per hour =
                                 $1,360.
Replace NLG...................  16 work-hours x         35,000  36,360................  3,163,320.
                                 $85 per hour =
                                 $1,360.

[[Page 8873]]

 
Replace associated components.  Up to 4 work-            4,000  Up to 4,340...........  Up to 377,580.
                                 hours x $85 per
                                 hour = $340.
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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:

2025-01-01 Britten-Norman Aerospace Ltd.: Amendment 39-22925; Docket 
No. FAA-2024-1299; Project Identifier MCAI-2023-00237-A.

(a) Effective Date

    This airworthiness directive (AD) is effective March 11, 2025.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Britten-Norman Aerospace Ltd. airplanes, 
certificated in any category, fitted with Fairey Hydraulics Ltd or 
Britten-Norman Aircraft landing gear and associated landing gear 
components, identified in paragraphs (c)(1) and (2) of this AD.
    (1) Model BN-2, BN-2A, BN-2A-2, BN-2A-3, BN-2A-6, BN-2A-8, BN-
2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-27, BN-2B-20, BN-2B-21, 
BN-2B-26, BN-2B-27, BN-2T, BN2T-4R, and BN2T-4S airplanes.
    (2) Model BN2A MK. III, BN2A MK. III-2, and BN2A MK. III-3 
airplanes.

(d) Subject

    Joint Aircraft System Component (JASC) Code 3200, Landing Gear 
System.

(e) Unsafe Condition

    This AD was prompted by the determination that in order to 
ensure the continued structural integrity of certain landing gear 
and associated components, it is necessary to require removal of 
these components from service prior to exceeding established fatigue 
lives. Exceeding the established fatigue life, if not addressed, 
could result in failure of the structural integrity of the landing 
gear and associated components, which could result in damage to the 
airplane and injury to occupants.

(f) Compliance

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

(g) Definitions

    For the purpose of this AD:
    (1) An ``affected part'' is a main landing gear (MLG), nose 
landing gear (NLG), or component identified in Table 1, 2, or 3 of 
Section 6 in Britten-Norman SB 298, Issue 3, dated July 7, 2023 
(Britten-Norman SB 298, Issue 3).
    (2) A ``part eligible for installation'' is an MLG, NLG, or 
component with a part that has been established to be below the 
associated fatigue life identified in Table 1, 2, or 3 of Section 6 
in Britten-Norman SB 298, Issue 3.

(h) Required Actions

    (1) Within 30 days after the effective date of this AD, 
determine the number of landings accumulated on the affected parts. 
For an unknown number of landings, calculate the number based on 3 
landings per 1 hour time-in-service.
    (2) Before accumulating the number of landings (fatigue life) 
associated with the applicable affected part as identified in Table 
1, 2, or 3 of Section 6 in Britten-Norman SB 298, Issue 3, or within 
the next 30 days after the effective date of this AD, whichever 
occurs later, replace any affected part with a part eligible for 
installation.
    (3) Thereafter, replace any affected part with a part eligible 
for installation before accumulating the fatigue life, as identified 
in Table 1, 2, or 3 of Section 6 in Britten-Norman SB 298, Issue 3.

(i) Parts Installation Limitation

    As of the effective date of this AD, do not install a MLG, NLG, 
or associated component unless it is a part eligible for 
installation.

(j) 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 local Flight 
Standards District 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 (k) of 
this AD or email to: [email protected]. If mailing information, also 
submit information by email. Before using any approved AMOC, notify 
your appropriate principal inspector, or lacking a principal 
inspector, the manager of the local Flight Standards District 
Office/certificate holding district office.

(k) Additional Information

    For more information about this AD, contact Beenal Desai, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (609) 485-9930; email: 
[email protected].

[[Page 8874]]

(l) 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) Britten-Norman Service Bulletin SB 298, Issue 3, dated July 
7, 2023.
    (ii) [Reserved]
    (3) For Britten-Norman material identified in this AD, contact 
Britten-Norman Aerospace Ltd., Bembridge Airport, Bembridge, Isle of 
Wight, UK, PO35 5PR; phone: +44 20 3371 4000; email: 
norman.com">customer.support@britten-norman.com; website: britten-norman.com/approvals-technical-publications.
    (4) You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 901 Locust, Kansas 
City, MO 64106. For information on the availability of this material 
at the FAA, call (817) 222-5110.
    (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 January 2, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-02187 Filed 2-3-25; 8:45 am]
BILLING CODE 4910-13-P
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