DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-1015; Product Identifier 2018-SW-104-AD]
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 adopt a new airworthiness directive (AD)
for Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1
helicopters. This proposed AD would require determining the accumulated
hours time-in-service (TIS) of certain part-numbered main gearbox (MGB)
suspension bar attachment fittings (fittings) and bolts, and would
establish new life limits. This proposed AD is prompted by the outcome
of tests and analyses performed by Airbus Helicopters. The actions of
this proposed AD are intended to address an unsafe condition on these
products.

DATES: The FAA must receive comments on this proposed AD by February 7,
2020.

ADDRESSES: You may send comments by any of the following methods:

Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow the
online instructions for sending your comments electronically.

Fax: 202-493-2251.

Mail: Send comments to the U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590-0001.

Hand Delivery: Deliver to the "Mail" address between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

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-2019-1015;
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 proposed AD, the European Aviation Safety Agency (EASA) AD, the
economic evaluation, any comments received, and other information. The
street address for Docket Operations is listed above. Comments will be
available in the AD docket shortly after receipt.

For service information identified in this proposed rule, contact
Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 75052;
telephone 972-641-0000 or 800-232-0323; fax 972-641-3775; or at https://
www.airbus.com/helicopters/services/technical-support.html. You may
review the referenced service information at the FAA, Office of the
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321,
Fort Worth, TX 76177.

FOR FURTHER INFORMATION CONTACT: Matt Fuller, Senior Aviation Safety
Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA,
10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-5110;
email matthew.fuller@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to participate in this rulemaking by submitting
written comments, data, or views. The FAA also invites comments
relating to the economic, environmental, energy, or federalism impacts
that might result from adopting the proposals in this document. The
most helpful comments reference a specific portion of the proposal,
explain the reason for any recommended change, and include supporting
data. To ensure the docket does not contain duplicate comments,
commenters should send only one copy of written comments, or if
comments are filed electronically, commenters should submit only one
time.

The FAA will file in the docket all comments that the FAA receives,
as well as a report summarizing each substantive public contact with
FAA personnel concerning this proposed rulemaking. Before acting on
this proposal, the FAA will consider all comments the FAA receives on
or before the closing date for comments. The FAA will consider comments
filed after the comment period has closed if it is possible to do so
without incurring expense or delay. The FAA may change this proposal in
light of the comments the FAA receives.

Discussion

EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD No. 2018-0260, dated December 3,
2018 (EASA AD 2018-0260), to correct an unsafe condition for Airbus
Helicopters (formerly Eurocopter, Eurocopter France, Aerospatiale)
Model AS 332 C, AS 332 C1, AS 332 L, and AS 332 L1 helicopters.

From review of reported Model EC 225 LP data, EASA advises that the
installation of the MGB upper deck fittings of the three MGB suspension
bars could lead to tightening torque loss on the fittings' attachment
screws (bolts). Due to design similarities, Model AS332L2 helicopters
could also be affected by the same installation condition.
Investigations determined that the life limits in the Airworthiness
Limitations Sections for the screws and fittings are valid if an "add-
on penalty factor" is applied. Based on these findings, EASA issued
EASA AD No. 2017-0133 dated July 27, 2017, and then superseded that AD
with EASA AD No. 2017-0189, dated September 22, 2017, for Model AS 332
L2 and EC 225 LP helicopters to address this condition.

Airbus Helicopter subsequently performed testing on Model AS 332 C,
AS 332 C1, AS 332 L, and AS 332 L1 helicopters due to design
similarities, and determined a life limit reduction of the MGB
suspension bar fittings and screws was necessary for these model
helicopters. Accordingly, EASA AD 2018-0260 was issued for these model
helicopters to require determining the accumulated service life of the
affected parts and to introduce new life limits.

EASA states that this condition, if not corrected, could lead to
structural failure of the MGB suspension bar fittings and screws,
possibly resulting in detachment of the MGB suspension bars.

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 of the
unsafe condition described in its AD. The FAA is proposing this AD
after evaluating all known relevant information and determining that an
unsafe condition is likely to exist or develop on other products of the
same type design.

Related Service Information

The FAA reviewed Airbus Helicopters Alert Service Bulletin No.
AS332-01.00.90, Revision 0, dated November 11, 2018. This service
information specifies determining the accumulated hours TIS of certain
part-numbered rear MGB suspension bar fittings and screws. This service
information further specifies criteria to determine the initial
replacement compliance time of those parts and a new life limit for
those parts thereafter. This service information also establishes a
life limit for the front MGB attachment screws.

Proposed AD Requirements

This proposed AD would require, within 50 hours TIS, reviewing the
helicopter records to determine the total hours TIS of the MGB
suspension bar right-hand side (RH) rear fitting part number (P/N)
330A22-2702-07 and of the MGB suspension bar left-hand side (LH) rear
fitting P/N 330A22-2702-06. This proposed AD would initially require
removing from service the RH rear fitting and its bolts P/N 330A22-
0135-20 and the LH rear fitting and its bolts P/N 330A22-0135-20 based
on the accumulated total hours TIS of the fittings and other
conditions. Thereafter, this proposed AD would require removing from
service the RH rear fitting and its bolts at intervals not to exceed
1,470 hours TIS, removing from service the LH rear fitting at intervals
not to exceed 13,600 hours TIS, and removing from service the LH rear
bolts during each Major Inspection "G." This proposed AD would also
require removing from service the front bolts P/N 330A22-0134-20 during
each Major Inspection "G."

Differences Between This Proposed AD and the EASA AD

The EASA AD allows an option for the first MGB RH rear attachment
fitting replacement to inspect torque and specifies different
replacement compliance times based on the torque inspection results,
whereas this proposed AD does not.

Interim Action

The FAA considers this proposed AD to be an interim action. The
design approval holder is currently developing a modification that will
address the unsafe condition identified in this AD. Once this
modification is developed, approved, and available, the FAA might
consider additional rulemaking.

Costs of Compliance

The FAA estimates that this proposed AD affects 14 helicopters of
U.S. Registry. Labor costs are estimated at $85 per work-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
about 0.5 work-hour for an estimated cost of $43 per helicopter and
$602 for the U.S. fleet.

Replacing a rear MGB fitting and its set of four bolts would take
about 8 work-hours and parts would cost about $12,937, for an estimated
cost of $13,617 per replacement cycle.

Replacing a set of four MGB attachment bolts would take about 4
work-hours and parts would cost about $224, for an estimated cost of
$564 per replacement cycle.

Replacing a LH rear MGB fitting would take about 8 work-hours and
parts would cost about $12,713, for an estimated cost of $13,393 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.

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. 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.

The FAA prepared an economic evaluation of the estimated costs to
comply with this proposed AD and placed it in the AD docket.

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

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):