[Federal Register Volume 90, Number 98 (Thursday, May 22, 2025)]
[Proposed Rules]
[Pages 21871-21874]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-09094]


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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 90, No. 98 / Thursday, May 22, 2025 / 
Proposed Rules

[[Page 21871]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0909; Project Identifier MCAI-2023-00895-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 supersede Airworthiness Directive (AD) 
2019-19-13, which applies to certain Airbus Helicopters Model EC225LP 
helicopters. AD 2019-19-13 requires determining the total hours time-
in-service (TIS) of the free wheel shafts of certain main rotor 
gearboxes (MGBs), replacing the MGB or right-hand side (RH) free wheel 
shaft, installing placard(s), and revising the Rotorcraft Flight Manual 
(RFM) for the helicopter. Since the FAA issued AD 2019-19-13, an 
additional part-numbered MGB has been identified to have the same 
unsafe condition and the FAA determined that additional changes are 
necessary. This proposed AD would require the actions of AD 2019-19-13 
and, expand the applicability by adding the additional part-numbered 
MGB, change the requirement to determine the total hours TIS of a 
certain free wheel shaft, require repetitive replacement of the MGB or 
the RH free wheel shaft, change the requirements for who can replace 
parts, and expand the parts installation limitation conditions. 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-2025-0909; 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.
    Other Related Material: For the Airbus Helicopters material 
identified in this proposed AD, 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.

FOR FURTHER INFORMATION CONTACT: Frank Huynh, Aviation Safety Engineer, 
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (404) 
983-2588; 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-2025-0909; 
Project Identifier MCAI-2023-00895-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 Frank 
Huynh, 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 2019-19-13, Amendment 39-19749 (84 FR 56109, 
October 21, 2019) (AD 2019-19-13), for Airbus Helicopters Model EC225LP 
helicopters, with a MGB part number (P/N) 332A325001.XX, 332A325002.XX, 
or 332A325003.XX, with a main reduction gear module (main module), and 
with a certain modification installed. AD 2019-19-13 was prompted by 
European Union Aviation Safety Agency (EASA) AD No. 2019-0152-E, dated 
June 28, 2019 (EASA AD 2019-0152-E), issued by EASA, which is the 
Technical Agent for the Member States of the European Union, to correct 
an unsafe condition for Airbus Helicopters Model EC 225 LP helicopters.
    AD 2019-19-13 requires determining the total hours TIS of each free 
wheel shaft and depending on the calculation, replacing the MGB with an 
airworthy MGB or replacing the RH free wheel shaft. AD 2019-19-13 also 
requires installing placard(s) in full view of both pilots and revising 
the RFM for the

[[Page 21872]]

helicopter with one engine inoperative (OEI) OEI training procedures 
pertaining to the ``TRAINING IDLE'' switches. As an option, AD 2019-19-
13 specifies installing alternate MGB configurations that would 
constitute terminating action for the requirements of AD 2019-19-13.
    The FAA issued AD 2019-19-13 to detect and prevent wear of the 
ramps of the RH side free wheel shaft.

Actions Since AD 2019-19-13 Was Issued

    Since the FAA issued AD 2019-19-13, EASA issued EASA AD 2023-0148, 
dated July 19, 2023 (EASA AD 2023-0148) (also referred to as the MCAI), 
to supersede EASA AD 2019-0152-E. The MCAI states that since EASA AD 
2019-0152-E was issued, it was determined that an additional part-
numbered MGB is potentially affected by the same unsafe condition and 
expanded the affected parts by adding MGB P/N 332A32-5004-00 with main 
module P/N 332A32-5400-00 installed.
    Additionally, the FAA has determined that repetitive replacement of 
the MGB is necessary and is requiring repetitive replacement of the MGB 
or the RH free wheel shaft at the 1,000 total hours TIS threshold. The 
FAA is also updating the actions that require replacing certain parts 
under the supervision of a qualified Airbus Helicopter Specialist by 
removing the requirement for the specified specialist since the actions 
must be accomplished by persons authorized under 14 CFR 43.3. The FAA 
has also changed the information that specifies availability of an 
example of the placard required by this proposed AD. Further, the FAA 
expanded the parts installation limitation conditions. Lastly, this 
NPRM uses an updated format; as a result, paragraph identifiers have 
changed. Finally, the FAA removed the requirement to determine the 
total hours TIS of the left-hand (LH) free wheel shaft.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2025-0909.

Comments to AD 2019-19-13

    After AD 2019-19-13 was published, the FAA received a comment from 
one commenter. The following presents the comments received on the NPRM 
and the FAA's response to the comment.
    The commenter stated the FAA AD is not in line with the intention 
of the Airbus Helicopters Alert Service Bulletin or the EASA AD. 
Specifically, the commenter stated the restriction that required the 
use of the RH free wheel shaft total hours TIS if the LH and RH free 
wheel shaft hours are different is not listed by Airbus or applied by 
EASA. Furthermore, the commenter stated, there are cases where the LH 
free wheel shaft has higher hours TIS than the RH free wheel shaft and 
the helicopter is ``still flying as long as the RH Free wheel is under 
1000 TSI''.
    The FAA infers the commenter is requesting that the FAA remove all 
required actions involving the LH free wheel shaft from the NPRM. The 
FAA agrees and has removed all wording involving the LH free wheel 
shaft from this NPRM.

Related Material

    The FAA reviewed Airbus Helicopters Emergency Alert Service 
Bulletin No. EC225-04A016, Revision 4, dated June 19, 2023, which 
specifies procedures for determining the total hours TIS of the free 
wheel shafts, a life limit schedule, and procedures for replacing the 
MGB or RH free wheel shaft, and installing one or two labels (placards) 
in view of both pilots about OEI training procedures.

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. Except for minor editorial changes and any 
other changes described previously, 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 2019-
19-13, would require some of the actions required by AD 2019-19-03, and 
would require the actions discussed under ``Actions Since AD 2019-19-13 
was Issued.''
    This proposed AD would also require revising the existing RFM for 
the helicopter. Revising the existing RFM for the helicopter may be 
performed by the owner/operator (pilot) holding at least a private 
pilot certificate and must be entered into the aircraft records showing 
compliance with this action in accordance with 14 CFR 43.9(a) and 
91.417(a)(2)(v). The pilot may perform this action because it only 
involves revising the existing RFM by inserting pages, which is not 
considered a maintenance action.

Differences Between This Proposed AD and the MCAI

    This proposed AD would require revising the existing RFM for the 
helicopter, whereas the MCAI does not. The MCAI requires reporting 
information, whereas this proposed AD would not.

Interim Action

    The FAA considers that this proposed AD would be an interim action. 
If final action is later identified, the FAA might consider further 
rulemaking.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 28 helicopters of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD. Labor costs are estimated at $85 
per hour.
    Determining the total hours TIS of each free wheel shaft would take 
0.25 work-hour, for an estimated cost of $21 per helicopter and $588 
for the U.S. fleet.
    Installing placard(s) and revising the existing RFM for the 
helicopter would take 0.5 work-hour for an estimated cost of $43 per 
helicopter and $1,204 for the U.S. fleet.
    Replacing an MGB would take 40 work-hours and parts would cost 
$850,000 (overhauled), for an estimated cost of $853,400 per 
helicopter, per replacement cycle.
    Alternatively, replacing the RH free wheel shaft would take 4 work-
hours and parts would cost $24,021, for an estimated cost of $24,361 
per helicopter, per replacement cycle.

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.

[[Page 21873]]

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 2019-19-13, Amendment 39-19749 (84 
FR 56109, October 21, 2019); and
0
b. Adding the following new airworthiness directive:

Airbus Helicopters: Docket No. FAA-2025-0909; Project Identifier 
MCAI-2023-00895-R.

(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 2019-19-13, Amendment 39-19749 (84 FR 56109, 
October 21, 2019) (AD 2019-19-13).

(c) Applicability

    This AD applies to Airbus Helicopters Model EC225LP helicopters, 
certificated in any category, with the parts identified in 
paragraphs (c)(1) or (2) of this AD installed, with ``XX'' denoting 
any dash number.
    (1) With a main rotor gearbox (MGB) part number (P/N) 332A32-
5001-XX, 332A32-5002-XX, or 332A32-5003-XX, with a main reduction 
gear module (main module), with modification (MOD) 07-53016 (16-
roller free wheel of free wheel shaft P/N 332A322191.20) installed, 
P/N 332A32-5011-XX, 332A32-5012-XX, or 332A32-5013-XX.
    (2) With an MGB P/N 332A32-5004-XX with a main module P/N 
332A32-5400-00.

(d) Subject

    Joint Aircraft System Component (JASC) Code 6320, Main rotor 
gear box; and 6300, Main rotor drive system.

(e) Unsafe Condition

    This AD was prompted by a report of wear detected on the right-
hand side (RH) free wheel shaft. In addition, since AD 2019-19-13 
was issued, the FAA has determined that additional parts are 
affected by the same unsafe condition. The FAA is issuing this AD to 
prevent wear of the ramps of the right-hand side (RH) free wheel 
shaft. During an in-flight shutdown of the left-hand side engine, 
this unsafe condition, if not addressed, could result in reduced 
ability to transfer one engine inoperative (OEI) power from the RH 
engine to the main rotor, and subsequent reduced control of the 
helicopter.

(f) Compliance

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

(g) Required Actions

    (1) Within 10 hours time-in-service (TIS) after the effective 
date of this AD, determine the total hours TIS of the RH free wheel 
shaft since new or last RH free wheel shaft replacement during 
overhaul.
    (i) If the total hours TIS of the RH free wheel shaft is 1,000 
or more hours TIS, before further flight, replace the MGB or replace 
the RH free wheel shaft. Thereafter, before any RH free wheel shaft 
accumulates 1,000 total hours TIS, replace the MGB or replace the RH 
free wheel shaft.
    (ii) If the total hours TIS of the RH free wheel shaft is less 
than 1,000 hours TIS, before exceeding 1,000 hours TIS, and 
thereafter before any RH free wheel shaft accumulates 1,000 total 
hours TIS, replace the MGB or replace the RH free wheel shaft.
    (2) Within 10 hours TIS after the effective date of this AD:
    (i) Install one or two self-adhesive placards on the instrument 
panel in full view of the pilot and co-pilot with 6-millimeter red 
letters on a white background that state the information contained 
in figure 1 to paragraph (g)(2)(i) of this AD.

    Note 1 to paragraph (g)(2)(i): Figure 4 of Airbus Helicopters 
Emergency Alert Service Bulletin No. EC225-04A016, Revision 4, dated 
June 19, 2023, shows an example of this placard.


                     Figure 1 to Paragraph (g)(2)(i)
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
The use of ENG1 ``TRAINING IDLE'' switch is prohibited.
 
ENG2 ``TRAINING IDLE'' switch must be systematically used.
------------------------------------------------------------------------

    (ii) After installing the placard(s) required by paragraph 
(g)(2)(i) of this AD, before further flight, revise the limitations 
section of the existing Rotorcraft Flight Manual (RFM) for the 
helicopter by adding the information in figure 2 to paragraph 
(g)(2)(ii) of this AD, by inserting a copy of this AD, or by making 
pen-and-ink changes. The owner/operator (pilot) holding at least a 
private pilot certificate may revise the existing RFM and must enter 
compliance with this RFM revision into the helicopter maintenance 
records in accordance with 14 CFR 43.9 (a) and 14 CFR 
91.417(a)(2)(v). The record must be maintained as required by 14 CFR 
91.417, 121.380, or 135.439.

                    Figure 2 to Paragraph (g)(2)(ii)
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
The use of ENG1 ``TRAINING IDLE'' switch is prohibited.
 
ENG2 ``TRAINING IDLE'' switch must be systematically used.
 
Accomplishment of OEI training flight is allowed, provided that only
 ENG2 ``TRAINING IDLE'' switch is used for that purpose.
------------------------------------------------------------------------

    (3) For Airbus Helicopters Model EC225LP helicopters with parts 
identified in paragraph (c)(1) of this AD installed, with ``XX'' 
denoting any dash number, as an optional terminating action for the 
requirements of this AD, install MGB P/N 332A32-5001-XX, 332A32-
5002-XX, or 332A32-5003-XX, with a main module (12-roller free 
wheel), without MOD 07-53016 installed, P/N 332A32-5011-XX, 332A32-
5012-XX, or 332A32-5013-XX.

[[Page 21874]]

(h) Parts Installation Limitations

    As of the effective date of this AD, do not install the parts 
identified in paragraph (h)(1) or (2) of this AD, with ``XX'' 
denoting any dash number, on any helicopter unless the actions 
required by paragraph (g)(2) of this AD are accomplished.
    (1) MGB P/N 332A32-5001-XX, 332A32-5002-XX, or 332A32-5003-XX 
with a main module, with MOD 07-53016 (16-roller free wheel of free 
wheel shaft P/N 332A322191.20) installed, P/N 332A32-5011-XX, 
332A32-5012-XX, or 332A32-5013-XX.
    (2) An MGB P/N 332A32-5004-XX with a main module P/N 332A32-
5400-00.

(i) Credit for Previous Actions

    This paragraph provides credit for the actions required by 
paragraphs (g)(1) and (2) of this AD, if those actions were 
performed before the effective date of this AD in accordance with 
the material identified in paragraphs (i)(1) through (3) of this AD.
    (1) Airbus Helicopters Emergency Alert Service Bulletin (ASB) 
No. EC225-04A016, Revision 1, dated June 28, 2019.
    (2) Airbus Helicopters Emergency ASB EC225-04A016, Revision 2, 
dated July 23, 2019.
    (3) Airbus Helicopters Emergency ASB EC225-04A016, Revision 3, 
dated August 5, 2019.

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

(k) Additional Information

    (1) For more information about this AD, contact Frank Huynh, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (404) 983-2588; email: 
[email protected].
    (2) For Airbus Helicopters material 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

    None.

    Issued on May 15, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-09094 Filed 5-21-25; 8:45 am]
BILLING CODE 4910-13-P