DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-1131; Project Identifier MCAI-2020-00613-R]
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 all Airbus Helicopters Model AS350B, AS350BA, AS350B1, AS350B2,
AS350B3, AS350C, and AS350D helicopters; Model AS355E, AS355F, AS355F1,
AS355F2, AS355N, and AS355NP helicopters; and Model EC130B4 and EC130T2
helicopters. This proposed AD was prompted by a report of failed main
rotor hub-to-mast attachment screws. This proposed AD would require
determining whether the helicopter has been operated in a severe
environment since the last inspection of the main rotor hub-to-mast
attachment screws, an inspection of the main rotor hub-to-mast
attachment screws if the helicopter has been operated in a severe
environment, and replacement of the main rotor hub-to-mast attachment
screws if necessary, as specified in a European Aviation Safety Agency
(now European Union Aviation Safety Agency) (EASA) AD, which will be
incorporated by reference. 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 January 29,
2021.

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 material incorporated by reference (IBR) in this AD, contact
the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49
221 8999 000; email: ADs@easa.europa.eu; internet: www.easa.europa.eu.
You may find this IBR material on the EASA website at https://ad.easa.
europa.eu. You may view this IBR material 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. It is also available in the AD
docket on the internet at https://www.regulations.gov by searching for
and locating Docket No. FAA-2020-1131.

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-2020-1131;
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, 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 FURTHER INFORMATION CONTACT: Hal Jensen, Aerospace Engineer,
Operational Safety Branch, FAA, 470 L'Enfant Plaza SW, Washington, DC
20024; phone: 202-267-9167; email: hal.jensen@faa.gov.

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-2020-1131; Project Identifier
MCAI-2020-00613-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 proposal.

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 Hal
Jensen, Aerospace Engineer, Operational Safety Branch, FAA, 470
L'Enfant Plaza SW, Washington DC 20024; phone: 202-267-9167; email:
hal.jensen@faa.gov. Any commentary that the FAA receives that is not
specifically designated as CBI will be placed in the public docket for
this rulemaking.

Discussion

The EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD 2017-0032, dated February 17, 2017;
corrected February 20, 2017 (EASA AD 2017-0032) (also referred to as
the Mandatory Continuing Airworthiness Information, or the MCAI), to
correct an unsafe condition for all Airbus Helicopters Model AS 350 B,
AS 350 BA, AS 350 BB, AS 350 B1, AS 350 B2, AS 350 B3, and AS 350 D
helicopters; AS 355 E, AS 355 F, AS 355 F1, AS 355 F2, AS 355 N, and AS
355 NP helicopters; and EC 130 B4 and EC 130 T2 helicopters. Model AS
350 BB helicopters are not certificated by the FAA and are not included
on the U.S. type certificate data sheet; this proposed AD therefore
does not include those helicopters in the applicability. This AD also
applies to Airbus Helicopter Model AS 350C helicopters because these
helicopters have a similar design and are included on the U.S. type
certificate data sheet.

This proposed AD was prompted by a report of failed main rotor hub-
to-mast attachment screws on a Model EC130B4 helicopter during a
scheduled maintenance inspection. The FAA is proposing this AD to
address failed main rotor hub-to-mast attachment screws, which could
lead to disconnection of the main rotor hub-to-mast attachment,
possibly resulting in loss of control of the helicopter. See the MCAI
for additional background information.

Related Service Information Under 1 CFR Part 51

EASA AD 2017-0032 describes procedures for determining whether the
helicopter has been operated in a severe environment since the last
inspection of the main rotor hub-to-mast attachment screws, an
inspection of the main rotor hub-to-mast attachment screws for
corrosion and damage (damage includes cracks, dents, and bolt
distortion) if the helicopter was operated in a severe environment, and
replacement of the main rotor hub-to-mast attachment screws if
necessary. This material 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.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to the bilateral agreement with the State of Design Authority, the FAA
has been notified of the unsafe condition described in the MCAI
referenced above. The FAA is proposing this AD because the FAA
evaluated all the relevant information and determined the unsafe
condition described previously is likely to exist or develop in other
products of the same type design.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified
in EASA AD 2017-0032, described previously, as incorporated by
reference, except for any differences identified as exceptions in the
regulatory text of this AD and except as discussed under "Differences
Between this Proposed AD and the MCAI."

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD
process, the FAA initially worked with Airbus and EASA to develop a
process to use certain EASA ADs as the primary source of information
for compliance with requirements for corresponding FAA ADs. The FAA has
since coordinated with other manufacturers and civil aviation
authorities (CAAs) to use this process. As a result, EASA AD 2017-0032
will be incorporated by reference in the FAA final rule. This proposed
AD would, therefore, require compliance with EASA AD 2017-0032 in its
entirety, through that incorporation, except for any differences
identified as exceptions in the regulatory text of this proposed AD.
Using common terms that are the same as the heading of a particular
section in the EASA AD does not mean that operators need comply only
with that section. For example, where the AD requirement refers to
"all required actions and compliance times," compliance with this AD
requirement is not limited to the section titled "Required Action(s)
and Compliance Time(s)" in the EASA AD. Service information specified
in EASA AD 2017-0032 that is required for compliance with EASA AD 2017-
0032 will be available on the internet at https://www.regulations.gov
by searching for and locating Docket No. FAA-2020-1131 after the FAA
final rule is published.

Differences Between This Proposed AD and the MCAI

EASA AD 2017-0032 does not apply to Airbus Helicopter Model AS350C
helicopters, which are included on the U.S. type certificate data
sheet. However, this proposed AD would apply to Airbus Helicopter Model
AS350C helicopters because those helicopters have a similar design to
the helicopters identified in EASA AD 2017-0032.

Where the service information specified in paragraph (3) of EASA AD
2017-0032 specifies to contact Airbus Helicopters if damage or
corrosion exceeds existing criteria, this proposed AD would require
replacing the affected screws using a method approved by the Manager,
International Validation Branch, FAA.

Costs of Compliance

The FAA estimates that this proposed AD affects 1,220 helicopters
of U.S. registry. The FAA estimates the following costs to comply with
this proposed AD:

Estimated Costs for Required Determination of Helicopter Operation in a Severe Environment

The FAA estimates that it would take about 1 hour per product to
comply with the proposed reporting requirement in this proposed AD. The
average labor rate is $85 per hour. Based on these figures, the FAA
estimates the cost of reporting the inspection results on U.S.
operators to be $103,700, or $85 per product.

The FAA estimates the following costs to do any necessary on-
condition actions that would be required based on the results of any
required actions. If a helicopter is determined to have been operated
in a severe environment, an inspection of the main rotor hub-to-mast
attachment screws will be required. If there is corrosion or damage to
any of the screws, replacement of the affected screws will be required.
The FAA has no way of determining the number of aircraft that might
need these on-condition actions:

Estimated Costs of On-Condition Actions

Paperwork Reduction Act

A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a current valid OMB control number. The control
number for the collection of information required by this proposed AD
is 2120-0056. The paperwork cost associated with this proposed AD has
been detailed in the Costs of Compliance section of this document and
includes time for reviewing instructions, as well as completing and
reviewing the collection of information. Therefore, all reporting
associated with this proposed AD is mandatory. Comments concerning the
accuracy of this burden and suggestions for reducing the burden should
be directed to: Information Collection Clearance Officer, Federal
Aviation Administration, 10101 Hillwood Parkway, Fort Worth, TX 76177-
1524.

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 above, 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: