DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0882; Product Identifier 2018-SW-113-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 inspecting the attachment
screws of each main gearbox (MGB) suspension bar rear attachment
fitting, and depending on the outcome, applying a sealing compound,
performing further inspections, and replacing affected parts. This
proposed AD is prompted by reports of an elongated attachment screw and
loss of tightening torque of the nut. 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 January 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-
0882; 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 received 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 received.

Discussion

EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD No. 2018-0282, dated December 19,
2018 (EASA AD 2018-0282), to correct an unsafe condition for Airbus
Helicopters (formerly Eurocopter, Eurocopter France, Aerospatiale)
Model AS332C, AS332C1, AS332L, and AS332L1 helicopters, delivered to
the first owner or customer before September 1, 2018, and with
attachment screws part number (P/N) 330A22013520 installed with MGB
right hand (RH) side rear attachment fitting P/N 330A22270207 and left
hand (LH) side rear attachment fitting P/N 330A22270206 of the MGB
suspension bars.

EASA advises that occurrences were reported of elongated attachment
screws and loss of tightening torque of the nut installed on the
affected part. EASA also advises that an investigation is ongoing to
determine the root cause of this event. EASA states this condition
could lead to structural failure of an MGB rear attachment fitting and
possibly result in detachment of an MGB suspension bar. Accordingly,
EASA AD 2018-0282 requires a one-time inspection of each attachment
screw for the number of threads that protrude beyond its bolt and
depending on the outcome, applying a sealing compound on the nuts, and
convex and concave washers; measuring the height of the protruding
threads; inspecting the tightening torque of the nuts; inspecting the
upper and lower convex and concave washers; measuring and inspecting
removed attachment screws; and replacing affected parts. EASA AD 2018-
0282 also requires reporting information to Airbus Helicopters. EASA
states EASA AD 2018-0282 is considered to be an interim action and
further AD action may follow.

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 determined that an
unsafe condition is likely to exist or develop on other products of the
same type designs.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Airbus Helicopters Alert Service Bulletin No.
AS332-53.02.04, Revision 0, dated November 21, 2018 which specifies
checking the number of threads that protrude beyond the bolt of the
attachment screws on the RH and LH rear attachment fittings of the MGB.
This service information also specifies a one-time inspection of the
affected parts and depending on findings, accomplishment of applicable
corrective actions.

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.

Proposed AD Requirements

This proposed AD would require inspecting each screw on the RH and
LH rear attachment by identifying the number of threads "F" that
extend beyond the nut. If there are 2 or less threads on each affected
part, or if there are 3 or more threads on any affected part with a
thread height less than 5 mm (0.196 in), this proposed AD would require
applying a sealing compound on the nuts, and convex and concave
washers. If there are 3 or more threads on any affected part with a
thread height of 5 mm (0.196 in) or more, this proposed AD would
require removing the nut and inspecting the convex and concave washers
for bent parts and corrosion. If any washers are bent or corroded, this
proposed AD would require removing the washers from service. If the
length "L" measurement of any attachment screw is greater than 59.3
mm (2.334 in), this proposed AD would require replacing the attachment
fitting and the set of four screws.

Differences Between This Proposed AD and the EASA AD

The EASA AD requires the operator to perform a torque check and
report the value to Airbus, whereas this proposed AD would not.

Interim Action

The FAA considers this proposed AD 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 would affect 14 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.

Inspecting the number of threads and applying a sealing compound
would take about 3 work-hours for an estimated cost of $255 per
helicopter and $3,570 for the U.S. fleet.

Replacing an attachment fitting and the set of four screws would
take about 16 work-hours and parts would cost about $6,330 for an
estimated replacement cost of $7,690.

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):