DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0996; Project Identifier AD-2023-00365-A,Q,R,T;
Amendment 39-22917; AD 2024-26-02]
RIN 2120-AA64

Airworthiness Directives; Various Airplanes and Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2021-07-13
for certain Pacific Scientific Company rotary buckle assemblies
(buckles). AD 2021-07-13 required inspecting each specified buckle
including its buckle handle vane and prohibited installing affected
buckles. This AD was prompted by the publication of an updated service
bulletin, which revises the applicability based on date of manufacture
of the affected buckles. This AD retains certain requirements of AD
2021-07-13, reduces the applicability, and requires performing
corrective actions by complying with certain portions of the updated
service bulletin. The FAA is issuing this AD to address the unsafe
condition on these products.

DATES: This AD is effective March 7, 2025.

The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 7, 2025.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-0996; 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 Parker Meggitt material identified in this AD, contact
Parker Meggitt Services, 1785 Voyager Avenue, Simi Valley, CA 93063;
phone: (877) 666-0712; email: TechSupport@meggitt.com.

You may view this material at the FAA, Office of the
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321,
Fort Worth, TX 76177. For information on the availability of this
material at the FAA, call: (817) 222-5110.

Other Related Material: For other related Parker Meggitt material
identified in this AD, contact Parker Meggitt Services, at the Parker
Meggitt Services contact information under Material Incorporated by
Reference above.

FOR FURTHER INFORMATION CONTACT: Hal Jensen, Aviation Safety Engineer,
FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: (303) 342-
1080; email: hal.jensen@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2021-07-13, Amendment 39-21490 (86 FR
17703, April 6, 2021) (AD 2021-07-13). AD 2021-07-13 applied to Pacific
Scientific Company buckles part numbers 1111430 and 1111475, all dash
numbers, installed on but not limited to Bombardier Inc., Learjet Inc.,
Mitsubishi Heavy Industries, Ltd., Textron Aviation, Inc. (type
certificate (TC) previously held by Cessna Aircraft Company), and
Viking Air Limited (TC previously held by de Havilland, Inc.) model
airplanes and Airbus Helicopters (TC previously held by Eurocopter
France) model helicopters. The NPRM published in the Federal Register
on April 9, 2024 (89 FR 24742). The NPRM was prompted by a manufacturer
determination that the cracking on the buckle handle was caused by a
material process issue and stated that the issue was resolved in 2007.
Accordingly, the manufacturer published revised material to revise the
applicability by date of manufacture and clarify procedures. In the
NPRM, the FAA proposed to require revising the applicability to plastic
buckles with a date of manufacture on or before May 31, 2007, or
buckles whose date of manufacture cannot be determined, except not
those buckles repaired with the installation of an airworthy buckle
handle after May 31, 2007, and marked with a BLUE logo on the center
button. In the NPRM, the FAA also proposed to clarify that the unsafe
condition could result in occupants not being able to release the
buckle in certain emergency landing conditions. Furthermore, the FAA
proposed to require using the revised service bulletin to accomplish
its requirements and add a special flight permit limitation.

Lastly, the NPRM updated the contact information to obtain related
material, and the FAA proposed to move and update the contents of Note
1 in AD 2021-07-13 to the preamble of this AD.

Discussion of Final Airworthiness Directive

Comments

The FAA received comments from seven commenters. The commenters
were Air Wisconsin Airlines, American Airlines (AAL), All Nippon
Airways (ANA), Delta Air Lines, Inc., Horizon Air, Southwest Airlines,
and United Airlines (UAL). The following presents the comments received
on the NPRM and the FAA's response to each comment.

Requests To Correct the Date of the Related Material

Delta Air Lines, Inc. and Horizon Air requested the FAA revise Note
1 to paragraph (c)(1) of the Applicability paragraph to update the date
for Meggitt Service Information Letter SIL Restraint-25-002-2023, dated
January 24, 2023. The commenters stated the updated publication date of
this related material is September 25, 2023, and not January 24, 2023.

The FAA agrees and has revised the citations of that service
information letter in Note 1 to paragraph (c)(1) of this AD, as well as
the Other Related Material section in this final rule.

Request To Exclude Newly Manufactured Aircraft

Delta Airlines, Inc. stated that it is receiving newly-manufactured
airplanes with the restraint systems provided in the related material.
Delta Airlines, Inc. further commented that Meggitt information
specifies that buckles produced after May 2007 do not have the safety
concern and are considered airworthy. Accordingly, Delta Airlines, Inc.
requested the FAA revise paragraph (c)(1) of the proposed AD to exclude
these aircraft that are new into service as these aircraft will have
brand new buckles installed after 2007.

The FAA disagrees. The FAA determined because Meggitt is the
Technical Standard Order Authorization (TSOA) holder and does not hold
an approval for installation of the restraints, it is not responsible
for recording or controlling which aircraft airframes the applicable
restraint systems are installed on. Individual operators may request an
alternative method of compliance (AMOC) under the provisions of
paragraph (j) of this AD if they believe that the installed buckle on
their aircraft's restraint system is airworthy.

Requests To Exclude Buckles With a Metal Handle or BLUE Logo

Delta Airlines, Inc. requested the FAA revise paragraphs (c) and
(g)(3) of the proposed AD to exclude buckles having a metal handle. AAL
and UAL requested the FAA confirm that buckles with a BLUE logo,
regardless of the date of manufacturer or the date of repair, are
compliant.

The FAA partially agrees. The FAA agrees that buckles with a metal
handle or a BLUE logo on the center button are not subject to this AD.
The FAA disagrees with specifically stating in paragraphs (c) and
(g)(3) of this AD that buckles with a metal handle are excluded from
the AD because the additional wording is not necessary since the text
already specifies that applicable handles are plastic. However, for
clarification, the FAA has added a note to paragraph (c)(1) of this AD
specifying that this AD does not apply to metal buckles or buckles with
a BLUE logo on the center button.

Request To Exclude Buckles With a Yellow or Gold Logo and Missing Date
of Manufacture

Southwest Airlines stated that AD 2021-07-13 allowed "yellow/
gold" logo buttons with compliant plastic handles. Southwest Airlines
requests the FAA allow the option to continue the use of buckles that
were previously inspected and compliant per AD 2021-07-13 that have a
yellow or gold logo button but are missing the date of manufacturer due
to premature wear.

The FAA disagrees. AD 2021-07-13 did not reference buckles having a
yellow or gold logo on the center button. Therefore, the FAA has made
no changes to this final rule based on that comment.

Comment Regarding Allowable Buckle Vane Handle Thickness

ANA requested clarification regarding paragraph (g)(2) of the
proposed AD, which specifies that a buckle vane handle thickness of
0.125 inch or greater is unacceptable, whereas Meggitt Service Bulletin
SB 25-1111432, Revision 002, states that a thickness (less than or)
equal to 0.125 inch is acceptable.

The FAA acknowledges this comment and has revised paragraph (g)(2)
of this AD to require corrective action only if the buckle handle vane
thickness is greater than 0.125 inch and paragraph (g)(3) of this AD to
prohibit installing a buckle with a buckle handle vane thickness
greater than 0.125 inch.

Comments Regarding Credit for Previous Actions

AAL and Horizon Air requested the FAA revise paragraph (h) of the
proposed AD to allow credit for paragraph (g)(1) of the proposed AD if
those actions were previously accomplished in accordance with
previously issued related material.

The FAA agrees to allow credit for paragraph (g)(1) of this AD if
the inspection of the buckle handle for a crack was previously
accomplished in accordance with Pacific Scientific Service Bulletin SB
25-1111432, dated May 22, 2007 (SB 25-1111432); or Meggitt Service
Bulletin SB 25-1111432, Revision 001, dated May 20, 2021 (SB 25-1111432
Rev 001). The FAA has revised paragraph (h) of this AD accordingly.

Air Wisconsin Airlines and Southwest Airlines requested the FAA
revise paragraph (h) of the proposed AD to allow credit for paragraph
(g)(1) of the proposed AD, if the buckle handle inspection was
completed in accordance with AD 2021-07-13.

The FAA acknowledges these comments and infers concern that some
buckles may be inspected for a crack twice unnecessarily, once as
required by AD 2021-07-13 and again as required by this AD. Instead of
revising paragraph (h) of this AD for this credit, the FAA has revised
paragraph (g)(1) of this AD to clarify the requirement to inspect for a
crack, unless already done.

UAL stated the proposed AD allows credit for previous actions if
the thickness of the vane was measured using previous service bulletin
revisions. UAL requested the FAA clarify that measurement of the buckle
handle vane thickness or replacement of the buckle as required in
paragraph (g)(2) of the proposed AD would be credit for previous
actions.

The FAA agrees. The FAA is allowing credit for accomplishing the
procedures to measure the buckle handle vane thickness by following SB
25-1111432 or SB 25-1111432 Rev 001 if done before the effective date
of this AD, and the FAA is allowing credit for the resultant
measurement and, if required the replacement based on the buckle vane
thickness.

Delta Airlines stated the FAA AMOC approval letter AIR-730-21-207
allowed to first inspect the buckle for a BLUE logo or a metal
configuration, and if there was a BLUE logo or the buckle was metal, no
further inspections were required. Delta Airlines further stated that
Parker Meggitt material specified that buckles produced or repaired
after 2007 are marked with a BLUE logo on the center button, and these
buckles along with metal buckles are compliant per the previously
described AMOC. Accordingly, Delta Airlines requested the FAA revise
paragraph (h) of the proposed AD to include credit for paragraphs
(g)(1) and (g)(2) of the proposed AD if the inspection was accomplished
using FAA AMOC approval letter AIR-730-21-207, dated June 29, 2021.

The FAA disagrees. The applicability of this AD already limits the
applicability to plastic buckles and exempts buckles marked with a BLUE
logo on the center button, therefore this AD does not apply to metal
buckles and buckles marked with a BLUE logo on the center button. To
clarify this, the FAA has revised this AD by adding a note to the
applicability which specifies that this AD does not apply to metal
buckles or buckles with a BLUE logo on the center button. Additionally,
as proposed in the NPRM and as adopted in paragraph (j)(3) of this AD,
AMOCs approved for AD 2021-07-13 are approved as AMOCs for the
corresponding requirements of this AD. Therefore, the FAA has made no
changes to this final rule's requirements based on that comment.

Conclusion

The FAA reviewed the relevant data, considered any comments
received, and determined that air safety requires adopting the 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
other changes described previously, 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 Parker Meggitt Service Bulletin SB 25-1111432,
Revision 002, dated September 12, 2023 (SB 25-1111432 Rev 002), which
specifies procedures for inspecting certain buckles for a crack, and
measuring each buckle handle vane for correct thickness. SB 25-1111432
Rev 002 also specifies procedures for corrective actions, including but
not limited to, removing and returning the buckle assembly or restraint
assembly to Parker Meggitt for overhaul or replacement; and removing
the buckle assembly or restraint assembly and
replacing them with spare, new, or repaired assemblies. An applicable
buckle may be included as a component of a different part-numbered
restraint system assembly. Table 1 of SB 25-1111432 Rev 002 identifies
restraint system P/Ns that may be affected.

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 Meggitt Service Information Letter SIL
Restraint-25-002-2023, dated September 25, 2023, which specifies
procedures for locating the date of manufacture on various buckles.

Differences Between This AD and the Related Material

Where the related material specifies sending affected parts to the
manufacturer, this AD does not require that action. The related
material does not specify a compliance time to inspect for a crack or
measure for thickness, whereas this AD requires inspecting the buckle
handle for a crack within 6 months and measuring the buckle handle vane
thickness within 12 months.

Costs of Compliance

The FAA estimates that this AD affects up to 1,435 restraint
systems installed on aircraft of U.S. registry. Labor rates are
estimated at $85 per work-hour. Based on these numbers, the FAA
estimates the following costs to comply with this AD.

Inspecting a buckle handle for a crack and measuring thickness will
take a minimal amount of time for a nominal cost.

If required, replacing a buckle will take 0.5 work-hour and parts
will cost $636 for an estimated cost of $679 per buckle replacement. As
an option, replacing a restraint system will take 0.5 work-hour and
parts will cost $1,031 for an estimated cost of $1,074 per restraint
system replacement.

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

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]

2. The FAA amends Sec. 39.13 by:

a. Removing Airworthiness Directive 2021-07-13, Amendment 39-21490 (86
FR 17703, April 6, 2021); and
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b. Adding the following new airworthiness directive: