[Federal Register Volume 90, Number 99 (Friday, May 23, 2025)]
[Proposed Rules]
[Pages 22028-22031]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-09095]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0910; Project Identifier MCAI-2023-01167-R]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2020-06-13, which applies to certain Airbus Helicopters Model AS332C, 
AS332C1, AS332L, and AS332L1 helicopters. AD 2020-06-13 requires 
determining the accumulated hours time-in-service (TIS) of certain 
part-numbered main gearbox (MGB) suspension bar rear attachment 
fittings (fittings) and bolts and establishes reduced life limits. 
Since the FAA issued AD 2020-06-13, it was determined that modifying 
the MGB suspension bar fittings link and installing improved MGB 
suspension bar fitting bolts are necessary. This proposed AD would 
require modifying the MGB suspension bar link, installing newly-
designed bolts, and prohibit installing certain parts. The FAA is 
proposing this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this NPRM by July 7, 2025.

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-2025-0910; 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, the mandatory continuing airworthiness 
information (MCAI), any comments received, and other information. The 
street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For EASA material identified in this proposed AD, contact 
EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 
8999 000; email: [email protected]; website: easa.europa.eu. You may 
find this material on the EASA website at ad.easa.europa.eu.

[[Page 22029]]

     You may view this material at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-
321, Fort Worth, TX 76177. 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-2025-0910.

FOR FURTHER INFORMATION CONTACT: Camille Seay, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
phone: (817) 222-5149; 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 to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2025-0910; 
Project Identifier MCAI-2023-01167-R'' 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 the 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 
Camille Seay, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 
410, Westbury, NY 11590. Any commentary that the FAA receives which is 
not specifically designated as CBI will be placed in the public docket 
for this rulemaking.

Background

    The FAA issued AD 2020-06-13, Amendment 39-19882 (85 FR 19080, 
April 6, 2020) (AD 2020-06-13), for Airbus Helicopters Model AS332C, 
AS332C1, AS332L, and AS332L1 helicopters with an MGB suspension bar 
right-hand (RH) side rear fitting part number (P/N) 330A22-2702-07 and 
bolt P/N 330A22-0135-20, MGB suspension bar left-hand (LH) side rear 
fitting P/N 330A22-2702-06 and bolt P/N 330A22-0135-20, or MGB 
suspension bar front bolt P/N 330A22-0134-20 installed. AD 2020-06-13 
was prompted by an MCAI originated by EASA, which is the Technical 
Agent for the Member States of the European Union. EASA issued AD 2018-
0260, dated December 3, 2018 (EASA AD 2018-0260), to address MGB 
suspension bar fittings and bolts remaining in service beyond their 
fatigue life. From review of reported Model EC 225 LP data, EASA 
advised that the installation of the MGB upper deck fittings of the 
three MGB suspension bars (front, RH side rear, and LH side rear) could 
lead to tightening torque loss on the fittings' attachment screws 
(bolts). Due to design similarities, Model AS 332 C, AS 332 C1, AS 332 
L, and AS 332 L1 helicopters could also be affected by the same 
installation condition.
    AD 2020-06-13 requires determining the total hours TIS of the MGB 
suspension bar RH side and LH side rear fittings, removing these 
fittings and bolts from service based on the accumulated total hours 
TIS and other conditions, and thereafter removing these fittings and 
bolts from service within specific intervals. AD 2020-06-13 also 
requires removing the front bolts from service during each major 
inspection ``G.'' The FAA issued AD 2020-06-13 to prevent failure of an 
MGB attachment assembly, detachment of an MGB suspension bar, and 
consequent loss of helicopter control.

Actions Since AD 2020-06-13 Was Issued

    Since the FAA issued AD 2020-06-13, EASA superseded EASA AD 2018-
0260 and issued EASA AD 2023-0194, dated November 8, 2023 (EASA AD 
2023-0194), to address an unsafe condition on all Airbus Helicopters 
Model AS 332 C, AS 332 C1, AS 332 L, and AS 332 L1 helicopters. EASA AD 
2023-0194 stated that, following the loss of tightening torque of the 
attachment screws of the upper deck fittings of the three MGB 
suspension bars and previous interim action, Airbus Helicopters 
developed modification (mod) 0728496 (for helicopters with machined 
frames) and mod 0729200 (for helicopters with sheet metal frames), 
which improve the link of the fittings of the MGB suspension bars and 
include improved fitting screws. After EASA issued EASA AD 2023-0194, 
EASA superseded EASA AD 2023-0194 with EASA AD 2023-0194R1 Revision 1, 
dated March 19, 2025 (EASA AD 2023-0194R1) (also referred to as the 
MCAI). The MCAI states that since EASA AD 2023-0194 was issued, a new 
risk analysis determined the calendar time compliance time for the 
modification can be extended. The MCAI further states that EASA AD 
2023-0194R1 is considered to be an interim action. This condition, if 
not addressed, could lead to structural failure of an MGB attachment 
assembly, detachment of an MGB suspension bar, and consequent loss of 
control of the helicopter.
    The FAA is proposing this AD to address the unsafe condition on 
these products. You may examine the MCAI in the AD docket at 
regulations.gov under Docket No. FAA-2025-0910.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed EASA AD 2023-0194R1, which specifies procedures 
for determining the accumulated service life of the RH side and LH side 
rear fittings of the MGB suspension bars and repetitively replacing the 
RH side and LH side rear fittings and screws before exceeding 
accumulated service life limits. As an alternative to the first 
replacement of the RH side rear fittings and screws, if certain 
conditions are met, EASA AD 2023-0194R1 allows measuring the tightening 
torque, and depending on the measurement results, replacing affected 
parts with serviceable parts within extended compliance times. EASA AD 
2023-0194R1 also specifies procedures for replacing each MGB front 
fitting screw at the next major inspection (G) and modifying the 
helicopter to improve the link of the fittings of the MGB suspension 
bar, which includes installing MGB fitting screws with an improved 
design. EASA AD 2023-0194R1 prohibits installing certain parts on any 
helicopter. Finally, EASA AD 2023-0194R1 specifies procedures for a 
terminating action if the helicopter has been modified as defined in 
EASA AD 2023-0194R1 and provides credit for certain previously 
accomplished requirements.
    This material is reasonably available because the interested 
parties have access to it through their normal course

[[Page 22030]]

of business or by the means identified in the ADDRESSES section.

FAA's Determination

    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 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.

Proposed AD Requirements in This NPRM

    This proposed AD would retain none of the requirements of AD 2020-
06-13. This proposed AD would require accomplishing the actions 
specified in EASA AD 2023-0194R1, described previously, as incorporated 
by reference, except for any differences identified as exceptions in 
the regulatory text of this proposed AD. See ``Differences Between this 
AD and the MCAI'' for a discussion of the general differences included 
in this AD.

Explanation of Required Compliance Information

    In the FAA's ongoing efforts to improve the efficiency of the AD 
process, the FAA developed a process to use some civil aviation 
authority (CAA) ADs as the primary source of information for compliance 
with requirements for corresponding FAA ADs. The FAA has been 
coordinating this process with manufacturers and CAAs. As a result, the 
FAA proposes to incorporate EASA AD 2023-0194R1 by reference in the FAA 
final rule. This proposed AD would, therefore, require compliance with 
EASA AD 2023-0194R1 in its entirety through that incorporation, except 
for any differences identified as exceptions in the regulatory text of 
this proposed AD. Using common terms that are the same as the heading 
of a particular section in EASA AD 2023-0194R1 does not mean that 
operators need comply only with that section. For example, where the AD 
requirement refers to ``all required actions and compliance times,'' 
compliance with this AD requirement is not limited to the section 
titled ``Required Action(s) and Compliance Time(s)'' in EASA AD 2023-
0194R1. Material referenced in EASA AD 2023-0194R1 for compliance will 
be available at regulations.gov under Docket No. FAA-2025-0910 after 
the FAA final rule is published.

Differences Between This Proposed AD and the MCAI

    Where the MCAI allows an option of an inspection of the torque 
instead of replacement of the first MGB RH side rear fitting, which 
includes different replacement compliance times based on the torque 
inspection results, this proposed AD would not.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect eight helicopters of U.S. registry. Labor rates are estimated at 
$85 per hour. Based on these numbers, the FAA estimates the following 
costs to comply with this proposed AD.
    Determining the total hours TIS of the rear MGB fittings would take 
0.5 work-hour for an estimated cost of $43 per helicopter and $344 for 
the U.S. fleet.
    Replacing a RH rear MGB fitting and its set of four bolts would 
take 8 work-hours and parts would cost $3,589 for an estimated cost of 
$4,269 per helicopter and $34,152 for the U.S. fleet, per replacement 
cycle.
    Replacing a set of four LH rear MGB fitting bolts would take 4 
work-hours and parts would cost $100 for an estimated cost of $440 per 
helicopter and $3,520 for the U.S. fleet, per replacement cycle.
    Replacing a LH rear MGB fitting would take 8 work-hours and parts 
would cost $3,807 for an estimated cost of $4,487 per helicopter and 
$35,896 for the U.S. fleet, per replacement cycle.
    Replacing a set of front MGB fitting bolts (4 bolts per set) would 
take about 8 work-hours and parts would cost $98 for an estimated cost 
of $778 per helicopter and $6,224 for the U.S. fleet, per replacement 
cycle.
    Modifying the MGB suspension bar (LH side and RH side) would take 
56 work-hours and parts would cost $115,509 for an estimated cost of 
$120,269 per helicopter.
    The extent of corrective action that may needed if there is damage, 
a crack, or insufficient clearance found while modifying the MGB 
suspension bar could vary significantly from helicopter to helicopter. 
The FAA has no way of determining the cost to correct or repair each 
helicopter or the number of helicopters that may require repair.

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 that the 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.


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by:
0
a. Removing Airworthiness Directive 2020-06-13, Amendment 39-19882 (85 
FR 19080, April 6, 2020); and
0
b. Adding the following new airworthiness directive:

Airbus Helicopters: Docket No. FAA-2025-0910; Project Identifier 
MCAI-2023-01167-R.

[[Page 22031]]

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by July 7, 2025.

(b) Affected ADs

    This AD replaces AD 2020-06-13, Amendment 39-19882 (85 FR 19080, 
April 6, 2020).

(c) Applicability

    This AD applies to Airbus Helicopters Model AS332C, AS332C1, 
AS332L, and AS332L1 helicopters, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 6330, Main rotor 
transmission mount.

(e) Unsafe Condition

    This AD was prompted by tests and analyses performed by the 
manufacturer. The FAA is issuing this AD to prevent fatigue failure 
of the main gearbox (MGB) suspension bar attachment fittings and 
bolts by remaining in service beyond their fatigue life. The unsafe 
condition, if not addressed, could result in failure of an MGB 
attachment assembly, detachment of an MGB suspension bar, and 
consequent loss of control of the helicopter.

(f) Compliance

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

(g) Requirements

    Except as specified in paragraphs (h) and (i) of this AD: Comply 
with all required actions and compliance times specified in, and in 
accordance with, European Union Aviation Safety Agency AD 2023-
0194R1, dated March 19, 2025 (EASA AD 2023-0194R1).

    Note 1 to paragraph (g): EASA AD 2023-0194R1 and Airbus 
Helicopters material that is referenced in EASA AD 2023-0194R1 refer 
to MGB suspension bar attachment ``bolts'' as ``screws.''


    Note 2 to paragraph (g): Table No. 1 of Airbus Helicopters Alert 
Service Bulletin No. AS332-53.02.13, Revision 1, dated April 5, 
2024, identifies the helicopter group configurations referenced in 
EASA AD 2023-0194R1.

(h) Exceptions to EASA AD 2023-0194R1

    (1) Where EASA AD 2023-0194R1 requires compliance in terms of 
flight hours, this AD requires using hours time-in-service.
    (2) Where EASA AD 2023-0194R1 refers to its effective date, 
December 17, 2018 (the effective date of EASA AD 2018-0260, dated 
December 3, 2018), or November 22, 2023 (the effective date of EASA 
AD 2023-0194, dated November 8, 2023), this AD requires using the 
effective date of this AD.
    (3) Where the material referenced in EASA AD 2023-0194R1 
specifies discarding parts, this AD requires removing those parts 
from service.
    (4) This AD does not adopt paragraphs (3) through (5) of EASA AD 
2023-0194R1.
    (5) Where paragraphs (2) and (6) of EASA AD 2023-0194R1 state 
``paragraph 3.B.3,'' this AD requires replacing that text with 
``paragraphs 3.B.2. and 3.B.3.''
    (6) Where the modification ASB, as defined and referenced in 
EASA AD 2023-0194R1, specifies contacting Airbus Helicopters 
Technical Support if there is visible damage, a crack, or 
insufficient clearance after replacing hardware, this AD requires, 
before further flight, accomplishing further action in accordance 
with a method approved by the Manager, International Validation 
Branch, FAA; EASA; or Airbus Helicopters' EASA Design Organization 
Approval (DOA). If approved by the DOA, the approval must include 
the DOA-authorized signature.
    (7) Where the modification ASB, as defined and referenced in 
EASA AD 2023-0194R1, specifies to keep parts after removing, for 
this AD, keeping these parts is not required.
    (8) Where the modification ASB, as defined and referenced in 
EASA AD 2023-0194R1, specifies repairing X3855 frame drilling kit 
(also identified as a Guide having part number X530P8102101 and 
referred to as Item ``zz''), this AD prohibits using X3855 frame 
drilling kit for the actions required by this AD if there is any 
damage that consists of cracks, corrosion, lengthening or 
deformation of the rods or arms, or excessive wear.
    (9) Sections 11 through 14 in Appendix 4.A. of the modification 
ASB, as defined and referenced in EASA AD 2023-0194R1, are not 
required by this AD.
    (10) This AD does not adopt the Remarks section of EASA AD 2023-
0194R1.

(i) No Reporting Requirement

    Although the material referenced in EASA AD 2023-0194R1 
specifies to submit information to the manufacturer, this AD does 
not require these actions.

(j) Alternative Methods of Compliance (AMOCs)

    (1) 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 (k)(1) of this AD 
and email 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.

(k) Additional Information

    (1) For more information about this AD, contact Camille Seay, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (817) 222-5149; email: 
[email protected].
    (2) For material identified in this AD that is not incorporated 
by reference, contact Airbus Helicopters, 2701 North Forum Drive, 
Grand Prairie, TX 75052; phone: (972) 641-0000 or (800) 232-0323; 
fax: (972) 641-3775; website: airbus.com/en/products-services/helicopters/hcare-services/airbusworld.

(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) European Union Aviation Safety Agency (EASA) AD 2023-0194R1, 
dated March 19, 2025.
    (ii) [Reserved]
    (3) For EASA material identified in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 
000; email: [email protected]; website: easa.europa.eu. You may 
find this material on the EASA website at ad.easa.europa.eu.
    (4) You may view this material at FAA, Office of the Regional 
Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort 
Worth, TX 76177. 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 May 15, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-09095 Filed 5-22-25; 8:45 am]
BILLING CODE 4910-13-P