DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0554; Product Identifier 2016-SW-088-AD; Amendment
39-21245; AD 2020-19-04]
RIN 2120-AA64

Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
Leonardo S.p.a. (Leonardo) Model AB139 and AW139 helicopters. This AD
requires removing certain main gearbox (MGB) input modules from
service. This AD was prompted by the discovery that a batch of duplex
bearings, which are installed on the MGB input modules, are defective.
The actions of this AD are intended to address an unsafe condition on
these products.

DATES: This AD is effective October 15, 2020.

ADDRESSES: For service information identified in this final rule,
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://www.leonardocompany.com/en/home. You may view this service
information at the FAA, 10101 Hillwood Pkwy., 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 on the internet at https://www.regulations.
gov by searching for and locating Docket No FAA-2020-
0554; 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 AD, the European Aviation Safety Agency (now European Union
Aviation Safety Agency) (EASA) AD, 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.

FOR FURTHER INFORMATION CONTACT: Rao Edupuganti, Aviation Safety
Engineer, Regulations and Policy Section, Rotorcraft Standards Branch,
FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-
5110; email rao.edupuganti@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to Leonardo Model AB139
and AW139 helicopters with certain serial-numbered MGB input modules
part number (P/N) 3K6320A00135 or P/N 3K6320A00136 installed. The NPRM
published in the Federal Register on June 8, 2020 (85 FR 35018). The
NPRM proposed to require removing the affected MGB input modules from
service and prohibit installing the affected MGB input modules. The
proposed requirements were intended to address defective duplex
bearings on MGB input modules, which could result in damage including
corrosion and cracking, which could result in excessive heat of the
input module duplex ball bearing inner race and subsequent loss of
engine power and loss of helicopter control.
The NPRM was prompted by EASA AD No. 2016-0255R1, dated January 17,
2017 (EASA AD 2016-0255R1), issued by EASA, which is the Technical
Agent for the Member States of the European Union, to correct an unsafe
condition for Leonardo (formerly Finmeccanica S.p.A., AgustaWestland
Philadelphia Corporation, Agusta Aerospace Corporation) Model AB139 and
AW139 helicopters with certain serial-numbered MGB input modules P/N
3K6320A00135 or P/N 3K6320A00136 installed. EASA advises that the
supplier of a batch of duplex bearings installed on MGB input modules
reported that the bearings were defective, due to a quality control
issue. This condition, if not detected or corrected, could lead to
damage of the input module duplex ball bearing inner race, possibly
resulting in loss of engine power and reduced control of the
helicopter. Accordingly, EASA AD 2016-0255R1 requires removing the
affected MGB input modules from service.

Comments

The FAA gave the public the opportunity to participate in
developing this final rule. The FAA received one comment in support of
the NPRM.

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 issuing this AD after
evaluating all known relevant information and determining that an
unsafe condition is likely to exist or develop on other helicopters of
the same type designs.

Differences Between This AD and the EASA AD

The EASA AD requires returning affected parts and sending
information to Leonardo; however, this AD does not.

Related Service Information

The FAA reviewed Leonardo Helicopters Bollettino Tecnico No. 139-
303, dated September 20, 2016, which specifies replacing certain duplex
bearings on MGB left-hand and right-hand input modules on Model AB139
and AW139 helicopters.

Costs of Compliance

The FAA estimates that this AD affects 71 helicopters of U.S.
Registry. The FAA estimates that operators may incur the following
costs in order to comply with this AD. Labor costs are estimated at $85
per work-hour.
Replacing one input module takes about 60 work-hours and parts cost
about $84,847 for an estimated cost of $89,947 per input module.
Replacing two input modules takes about 100 work-hours and parts cost
about $169,694 for an estimated cost of $178,194 per two input modules.

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.

Adoption of 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 adding the following new airworthiness
directive (AD):