[Federal Register Volume 87, Number 76 (Wednesday, April 20, 2022)]
[Proposed Rules]
[Pages 23477-23480]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-08304]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0465; Project Identifier AD-2022-00330-R]
RIN 2120-AA64


Airworthiness Directives; Leonardo S.p.a. 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) 
2021-20-10, which applies to certain Leonardo S.p.a. Model AB139 and 
AW139 helicopters. AD 2021-20-10 requires removing from service a 
certain part-numbered main gearbox (MGB) spherical bearing lock nut 
(lock nut) that is installed on certain part-numbered MGBs and 
replacing it with a newly designed MGB lock nut. AD 2021-20-10 also 
prohibits installing any MGB with the affected MGB lock nut and 
prohibits installing any affected MGB lock nut on any helicopter. Since 
the FAA issued AD 2021-20-10, it was discovered that a part number (P/
N) was incorrectly listed and that the applicability needed to be 
clarified. This proposed AD would retain the requirements of AD 2021-
20-10 and would clarify the applicability. The FAA is proposing this AD 
to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by June 6, 
2022.

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 https://www.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.
    For service information identified in this NPRM, contact Leonardo 
S.p.A. Helicopters, Emanuele Bufano, Head of Airworthiness, Viale G. 
Agusta 520, 21017 C. Costa di Samarate (Va) Italy; telephone +39-0331-
225074; fax +39-0331-229046; or at https://customerportal.leonardocompany.com/en-US/. You may view this service 
information 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2022-0465; 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 European 
Union Aviation Safety Agency (EASA) AD, any comments received, and 
other information. The street address for Docket Operations is listed 
above.

[[Page 23478]]


FOR FURTHER INFORMATION CONTACT: Kristi Bradley, Program Manager, COS 
Program Management Section, Operational Safety Branch, Compliance & 
Airworthiness Division, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 
76177; telephone (817) 222-5110; 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 ADDRESSES. Include ``Docket No. FAA-2022-0465; Project Identifier 
AD-2022-00330-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 
https://www.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 
Kristi Bradley, Program Manager, COS Program Management Section, 
Operational Safety Branch, Compliance & Airworthiness Division, FAA, 
10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; 
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

    The FAA issued AD 2021-20-10, Amendment 39-21748 (86 FR 57574, 
October 18, 2021) (AD 2021-20-10), for Leonardo S.p.a. Model AB139 and 
AW139 helicopters, without MGB lock nut P/N 3G6320A09152 installed and 
with MGB P/N 3G6320A00131, 3G6320A00132, 3G6320A00133, 3G6320A00134, 
3G6320A00135, 3G6320A00136, 3G6320A22031, 4G6320A00132, or 4G6320A00133 
installed; or MGB P/N 3G320A00133 with serial number (S/N) M23, or MGB 
P/N 3G6320A00134, with S/N M6, N76, N92, P124, P129, P131, P162, P184, 
Q230, Q243, Q249, R272, V21, V39, V96, V163, V211, V241, V272, V281, 
V384, V386, or V622 installed; or MGB P/N 3G6320A00136 with S/N AW1, 
AW2, AW3, AW5, or AW10 installed.
    AD 2021-20-10 requires, within 100 hours time in service (TIS), or 
during the next scheduled MGB overhaul, whichever occurs first after 
the effective date of the AD, removing a certain part-numbered MGB lock 
nut from service and replacing it with a different part-numbered MGB 
lock nut. AD 2021-20-10 also prohibits installing an MGB having an 
affected MGB lock nut on any helicopter and also prohibits installing 
an affected MGB lock nut on any helicopter as of the effective date of 
the AD.
    AD 2021-20-10 was prompted by a series of EASA ADs beginning with 
EASA AD 2019-0036, dated February 15, 2019 (EASA AD 2019-0036), issued 
by EASA, which is the Technical Agent for the Member States of the 
European Union, to correct an unsafe condition for all serial-numbered 
Leonardo S.p.a. Helicopters (formerly Finmeccanica S.p.A, 
AgustaWestland S.p.A., Agusta S.p.A.; and AgustaWestland Philadelphia 
Corporation, formerly Agusta Aerospace Corporation) Model AB139 and 
AW139 helicopters. EASA advised that an occurrence was reported of a 
cracked MGB lock nut P/N 3G6310A09151, which is used to keep the 
planetary gears in position. EASA AD 2019-0036 required replacing each 
MGB lock nut with an airworthy MGB lock nut. EASA advised this 
condition, if not detected and corrected, could lead to failure of the 
MGB planetary gears, resulting in loss of control of the helicopter.
    After EASA issued EASA AD 2019-0036, an additional occurrence was 
reported of a cracked MGB lock nut P/N 3G6320A09151. Accordingly, EASA 
superseded EASA AD 2019-0036 with EASA AD 2019-0174, dated July 18, 
2019 (EASA AD 2019-0174), which retained the requirements of EASA AD 
2019-0036 but reduced the compliance times. After EASA issued EASA AD 
2019-0174, Leonardo Helicopters issued Alert Service Bulletin No. 139-
609, dated December 18, 2019, to provide instructions for replacing the 
affected MGB lock nut with MGB lock nut P/N 3G6320A09152, which has a 
redesigned flange reducing the stress at the bearing nut locations 
where cracks were detected.
    Accordingly, EASA then issued EASA AD 2020-0011, dated January 29, 
2020, and corrected January 30, 2020 (EASA AD 2020-0011), which 
superseded EASA AD 2019-0174, and partially retained the requirements 
of EASA AD 2019-0174. EASA AD 2020-0011 revised the compliance times in 
EASA AD 2019-0174, required replacing each affected MGB lock nut with a 
newly designed MGB lock nut, and prohibited installing an affected MGB 
on any helicopter. After EASA issued EASA AD 2020-0011, EASA identified 
certain MGB part numbers that were inadvertently categorized 
incorrectly and therefore listed in the wrong group of helicopters. 
Accordingly, EASA issued EASA AD 2020-0011R1, dated November 20, 2020 
(EASA AD 2020-011R1), thereby revising EASA AD 2020-0011. EASA AD 2020-
0011R1 retained the requirements of EASA AD 2020-0011 and corrected 
Appendix 1 of EASA AD 2020-0011.
    After EASA issued EASA AD 2020-0011R1, Leonardo Helicopters issued 
Alert Service Bulletin No. 139-609, Revision A, dated April 13, 2021, 
which identifies an additional part-numbered MGB, which is also 
affected by the unsafe condition. Accordingly, EASA superseded EASA AD 
2020-0011R1 with EASA AD 2021-0121, dated May 4, 2021 (EASA AD 2021-
0121). EASA AD 2021-0121 adds an additional part-numbered MGB with a 
certain S/N to the list of affected parts. EASA AD 2021-0121 retains 
the requirements of EASA AD 2020-0011R1, and corrects Table 1 and 
Appendix 1 of EASA AD 2020-0011R1.
    Accordingly, EASA AD 2021-0121 requires replacing each affected MGB 
lock nut with a newly designed MGB lock nut, and prohibits installing 
an affected MGB on any helicopter.

Actions Since AD 2021-20-10 Was Issued

    Since the FAA issued AD 2021-20-10, it was discovered that MGB P/N 
3G6320A00133 is incorrectly listed as MGB P/N 3G320A00133 in both the 
preamble and applicability paragraph of the AD. Also, the FAA 
determined that

[[Page 23479]]

all MGBs, regardless of S/N, are affected by the unsafe condition. 
Therefore, this proposed AD would remove any reference to S/Ns in the 
applicability. In addition, this proposed AD includes the total U.S. 
fleet costs, which were inadvertently excluded in AD 2021-20-10.

FAA's Determination

    These helicopters have been approved by EASA and are approved for 
operation in the United States. Pursuant to the FAA's bilateral 
agreement with the European Union, EASA has notified the FAA about the 
unsafe condition described in its AD. The FAA is proposing this AD 
after evaluating all known relevant information and determining that 
the unsafe condition described previously is likely to exist or develop 
on other helicopters of the same type designs.

Related Service Information Under 1 CFR Part 51

    This proposed AD would require Leonardo Helicopters Alert Service 
Bulletin No. 139-609, Revision A, dated April 13, 2021, which the 
Director of the Federal Register approved for incorporation by 
reference as of November 22, 2021 (86 FR 57574, October 18, 2021).
    This service information 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 Service Information

    The FAA also reviewed Leonardo Helicopters Alert Service Bulletin 
No. 139-567, Revision B, dated October 18, 2019, which provides 
additional information for replacing the MGB lock nut.

Proposed AD Requirements in This NPRM

    This proposed AD would retain all of the requirements of AD 2021-
20-10.

Differences Between This Proposed AD and EASA AD 2021-0121

    EASA AD 2021-0121 requires a compliance time based on number of 
landings, whereas this proposed AD would require a compliance time 
based on hours TIS. The service information referenced in EASA AD 2021-
0121 requires submitting certain information and parts to Leonardo, 
whereas this proposed AD would not. EASA AD 2021-0121 applies to all 
serial-numbered Model AB139 and AW139 helicopters, whereas this 
proposed AD would apply to all Model AB139 and AW139 helicopters, 
regardless of S/N, with a certain part-numbered MGB lock nut and MGB 
installed.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 130 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.
    Replacing each affected MGB lock nut with a newly designed MGB lock 
nut would take about 190 work-hours (during next MGB overhaul) and 
parts would cost about $7,600 for an estimated cost of $23,750 per 
helicopter and $3,087,500 for the U.S. fleet.

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, 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:
0
a. Removing Airworthiness Directive 2021-20-10, Amendment 39-21748 (86 
FR 57574, October 18, 2021); and
0
b. Adding the following new airworthiness directive:

Leonardo S.p.a.: Docket No. FAA-2022-0465; Project Identifier AD-
2022-00330-R.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) action by June 6, 2022.

(b) Affected ADs

    This AD replaces AD 2021-20-10, Amendment 39-21748 (86 FR 57574, 
October 18, 2021) (AD 2021-20-10).

(c) Applicability

    This AD applies to Leonardo S.p.a. Model AB139 and AW139 
helicopters, certificated in any category, with a main rotor gearbox 
(MGB) part number (P/N) 3G6320A00131, 3G6320A00132, 3G6320A00133, 
3G6320A00134, 3G6320A00135, 3G6320A00136, 3G6320A22031, 
4G6320A00132, or 4G6320A00133, and MGB spherical bearing lock nut 
(lock nut) P/N 3G6320A09151 installed.

(d) Subject

    Joint Aircraft Service Component (JASC) Code: 6320, Main Rotor 
Gearbox.

(e) Unsafe Condition

    This AD was prompted by a cracked MGB lock nut. The FAA is 
issuing this AD to replace an affected MGB lock nut with a new MGB 
lock nut. The unsafe condition, if not addressed, could result in 
failure of the MGB planetary gears, resulting in loss of control of 
the helicopter.

(f) Compliance

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

(g) Required Actions

    (1) Within 100 hours time-in-service, or during the next 
scheduled MGB overhaul, whichever occurs first after November 22, 
2021 (the effective date of AD 2021-20-10),

[[Page 23480]]

remove each MGB lock nut P/N 3G6320A09151 from service and replace 
with MGB lock nut P/N 3G6320A09152 in accordance with Annex A, steps 
1 through 17, of Leonardo Helicopters Alert Service Bulletin No. 
139-609, Revision A, dated April 13, 2021, except you are not 
required to send parts to Leonardo Helicopters.

    Note to paragraph (g)(1):  Leonardo Helicopters service 
information refers to an MGB lock nut as a ring nut.

    (2) As of November 22, 2021 (the effective date of AD 2021-20-
10), do not install any MGB having MGB lock nut P/N 3G630A09151 on 
any helicopter, and do not install any MGB lock nut P/N 3G630A09151 
on any helicopter.

(h) Special Flight Permits

    Special flight permits are prohibited.

(i) 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 (j)(1) of 
this AD. Information may be emailed 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.

(j) Related Information

    (1) For more information about this AD, contact Kristi Bradley, 
Program Manager, COS Program Management Section, Operational Safety 
Branch, Compliance & Airworthiness Division, FAA, 10101 Hillwood 
Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email 
[email protected].
    (2) For service information identified in this AD, contact 
Leonardo S.p.A. Helicopters, Emanuele Bufano, Head of Airworthiness, 
Viale G. Agusta 520, 21017 C. Costa di Samarate (Va) Italy; 
telephone +39-0331-225074; fax +39-0331-229046; or at https://customerportal.leonardocompany.com/en-US/. You may view this 
referenced service information 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.
    (3) The subject of this AD is addressed in European Union 
Aviation Safety Agency (EASA) AD 2021-0121, dated May 4, 2021. You 
may view the EASA AD at https://www.regulations.gov in Docket No. 
FAA-2022-0465.

    Issued on April 13, 2022.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2022-08304 Filed 4-19-22; 8:45 am]
BILLING CODE 4910-13-P


