DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0652; Product Identifier 2019-SW-066-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 main rotor
(M/R) hub assembly (hub) phonic wheel lock washer (lock washer) for
correct installation and depending on the outcome, repairing or
replacing the M/R hub. This proposed AD was prompted by reported
occurrences of M/R revolutions per minute ("NR") sensor fluctuations.
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 August 31,
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-2020-0652;
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 Union Aviation Safety Agency (previously
European Aviation Safety Agency) (EASA) AD, 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
view 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 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.

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 file in the docket all comments received, 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.

Confidential Business Information

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 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. Any commentary
that the FAA receives which is not specifically designated as CBI will
be placed in the public docket for this rulemaking.

Discussion

EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD No. 2019-0172, dated July 18, 2019,
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 with M/R hub part number 332A31-
0001-00, P/N 332A31-0001-01, P/N 332A31-0001-02, P/N 332A31-0001-03, P/
N 332A31-0001-04, P/N 332A31-0001-05, or P/N 332A31-0001-06 installed.
EASA advises of reported occurrences of "NR" sensor fluctuation and
subsequent investigation identifying incorrect positioning of the M/R
hub phonic wheel due to incorrect installation of the M/R mast nut
press screws during maintenance of the M/R hubs. The investigation also
determined that this incorrect installation can be identified by
inspecting the lock washer position. EASA advises that this condition,
if not detected and corrected, could lead to failure of M/R hub
components, possibly resulting in loss of helicopter control.

Accordingly, the EASA AD requires a one-time inspection of the lock
washer position and depending on findings, replacing the M/R hub.

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

Related Service Information Under 1 CFR Part 51

The FAA reviewed Airbus Helicopters Alert Service Bulletin No.
AS332-62.00.76, Revision 0, dated May 27, 2019, for civilian Model
AS332C, C1, L, and L1 and military Model AS332B, B1, F1, M, and M1
helicopters. This service information specifies inspecting the position
of the M/R hub lock washer.

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, within 55 hours time-in-service,
removing at least one "NR" sensor and borescope inspecting for the
correct height of the lock washer through the hole of the removed
"NR" sensor. This proposed AD would then require installing an "NR"
sensor(s), and if the lock washer height is not correct, also repairing
or replacing the M/R hub with an airworthy M/R hub.

This proposed AD would also prohibit the installation of an
affected M/R hub unless it has successfully passed the required
inspection for correct lock washer installation.

Differences Between This Proposed AD and the EASA AD

The EASA AD requires using a flashlight and visually inspecting the
position of the lock washer, and further specifies that using an
endoscope can facilitate that inspection. This proposed AD would
require borescope inspecting for the correct height of the lock washer
instead. After inspecting, the EASA AD requires reinstalling the
removed "NR" sensor(s), while this proposed AD would require
installing airworthy "NR" sensor(s) instead. If the lock washer is in
an incorrect position, the EASA AD requires replacing the M/R hub,
whereas this proposed AD would require repairing or replacing the M/R
hub with an airworthy M/R hub instead.

Costs of Compliance

The FAA estimates that this proposed AD affects 11 helicopters of
U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on
these numbers, the FAA estimates that operators may incur the following
costs in order to comply with this proposed AD.

Removing an "NR" sensor and borescope inspecting would take about
0.5 work-hour for an estimated cost of $43 per helicopter and $473 for
the U.S. fleet.

Repairing the M/R hub would take about 10 work-hours and parts
would cost up to about $3,000 for an estimated cost of up to $3,850 and
replacing the M/R hub would take about 8 work-hours and parts would
cost about $50,000 for an estimated cost of $50,680.

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.

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):