```

[Federal Register Volume 90, Number 11 (Friday, January 17, 2025)]
[Proposed Rules]
[Pages 5748-5751]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-01100]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0007; Project Identifier MCAI-2023-00998-R]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all

[[Page 5749]]

Airbus Helicopters Model SA341G and SA342J helicopters. This proposed 
AD was prompted by reports of corrosion on the contact surfaces of the 
tail rotor inclined and horizontal drive shaft flanges. This proposed 
AD would require repetitively inspecting the inclined and horizontal 
drive shaft flanges and, depending on the results, replacing the 
inclined or horizontal drive shaft. This proposed AD would also 
prohibit installing certain inclined and horizontal drive shafts unless 
certain requirements are met, as specified in a European Union Aviation 
Safety Agency (EASA) AD, which is proposed for incorporation by 
reference. The FAA is proposing this AD to address the unsafe condition 
on these products.

DATES: The FAA must receive comments on this NPRM by March 3, 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-2025-0007; 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 the EASA material on the EASA website at ad.easa.europa.eu.
     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 
regulation.gov under Docket No. FAA-2025-0007.

FOR FURTHER INFORMATION CONTACT: Evan Weaver, Aviation Safety Engineer, 
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 
946-4152; 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-2025-0007; 
Project Identifier MCAI-2023-00998-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 this 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 Evan 
Weaver, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (316) 946-4152; email: 
[email protected]. Any commentary that the FAA receives which is 
not specifically designated as CBI will be placed in the public docket 
for this rulemaking.

Background

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2023-0168, dated August 31, 2023 
(EASA AD 2023-0168) (also referred to as the MCAI), to correct an 
unsafe condition on all Airbus Helicopters Model SA 341 G and SA 342 J 
(Gazelle) helicopters. The MCAI states that there have been several 
reports of corrosion on the contact surfaces of the tail rotor inclined 
and horizontal drive shaft flanges. More detailed non-destructive 
testing indicated pitting corrosion on the mating faces of several 
flanges and further investigation revealed various regions of 
intergranular failure beneath the surface of corrosion pits. The unsafe 
condition, if not addressed, could result in the failure of the tail 
rotor drive and subsequent loss of control of the helicopter.
    The FAA is issuing this proposed 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-2025-0007.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed EASA AD 2023-0168, which requires repetitively 
inspecting the flanges of certain part-numbered inclined and horizontal 
drive shafts for corrosion. If corrosion is found, EASA AD 2023-0168 
requires replacing the affected inclined or horizontal drive shaft. 
EASA AD 2023-0168 also prohibits installing an affected inclined or 
horizontal drive shaft on any helicopter unless it is a serviceable 
part as defined within. 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.

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 require accomplishing the actions specified 
in EASA AD 2023-0168, described previously, as incorporated by 
reference, except for any differences

[[Page 5750]]

identified as exceptions in the regulatory text of this proposed AD and 
except as discussed under ``Differences Between This NPRM and the 
MCAI.''

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 2023-0168 by reference in the FAA 
final rule. This proposed AD would, therefore, require compliance with 
EASA AD 2023-0168 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 2023-0168 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-
0168. Material required by EASA AD 2023-0168 for compliance will be 
available at regulations.gov under Docket No. FAA-2025-0007 after the 
FAA final rule is published.

Differences Between This NPRM and the MCAI

    The material referenced in the MCAI specifies sending corroded 
parts to Airbus Helicopters, whereas this proposed AD would not require 
that action.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 63 helicopters 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 proposed AD.
    Visually inspecting the inclined and horizontal drive shaft flanges 
would take 4 work-hours for an estimated cost of $340 per helicopter 
and $21,420 for the U.S. fleet, per inspection cycle. If required, 
replacing the inclined or horizontal drive shaft would take 4 work-
hours and parts would cost $17,900 (inclined drive shaft) or $35,500 
(horizontal drive shaft), for an estimated cost of $18,240 or $35,840 
per helicopter.

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 this 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 adding the following new airworthiness 
directive:

Airbus Helicopters: Docket No. FAA-2025-0007; Project Identifier 
MCAI-2023-00998-R.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by March 3, 2025.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Airbus Helicopters Model SA341G and SA342J 
helicopters, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 6510, Tail Rotor 
Drive Shaft.

(e) Unsafe Condition

    This AD was prompted by reports of corrosion on the contact 
surfaces of the tail rotor inclined and horizontal drive shaft 
flanges. The FAA is issuing this AD to detect and address corrosion 
on the inclined and horizontal drive shaft flanges. The unsafe 
condition, if not addressed, could result in the failure of the tail 
rotor drive and subsequent 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 2023-0168, 
dated August 31, 2023 (EASA AD 2023-0168).

(h) Exceptions to EASA AD 2023-0168

    (1) Where EASA AD 2023-0168 requires compliance in terms of 
flight hours, this AD requires using hours time-in-service.
    (2) Where EASA AD 2023-0168 refers to its effective date, this 
AD requires using the effective date of this AD.
    (3) Where the material referenced in paragraph (2) of EASA 2023-
0168 specifies sending corroded inclined or horizontal drive shaft 
to Airbus Helicopters, this AD does not require that action.
    (4) This AD does not adopt the ``Remarks'' section of EASA AD 
2023-0168.

(i) No Reporting Requirement

    Although the material referenced in EASA AD 2023-0168 specifies 
to submit certain information to the manufacturer, this AD does not 
require that action.

(j) Special Flight Permits

    Special flight permits are prohibited.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation Branch, FAA, has the 
authority to approve

[[Page 5751]]

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 (l) 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 local flight standards district office/certificate holding 
district office.

(l) Additional Information

    For more information about this AD, contact Evan Weaver, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (316) 946-4152; email: 
[email protected].

(m) 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 2023-0168, 
dated August 31, 2023.
    (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 EASA material on the EASA website at ad.easa.europa.eu.
    (4) 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.
    (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 13, 2025.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-01100 Filed 1-16-25; 8:45 am]
BILLING CODE 4910-13-P
```