DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-1183; Project Identifier 2019-SW-008-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 certain Airbus Helicopters Model EC 155B, EC155B1, SA-365N, SA-
365N1, AS-365N2, and AS 365 N3 helicopters, as identified in a European
Aviation Safety Agency (now European Union Aviation Safety Agency)
(EASA) AD. This proposed AD was prompted by a report of an in-flight
loss of engine and main gearbox (MGB) cowlings. This proposed AD would
require inspecting the MGB fixed cowling front fitting (MGB front
fitting), and depending on findings, corrective action. This proposed
AD would also require a new modification, which would constitute a
terminating action for the inspection. These proposed AD requirements
are as specified in an EASA AD, which is proposed for incorporation by
reference (IBR). 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 April 19,
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 that is proposed for IBR in this AD, contact the EASA,
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999
000; email ADs@easa.europa.eu; internet www.easa.europa.eu. You may
find this material on the EASA website at https://ad.easa.europa.eu.
You may view this 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-2020-1183.

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-2020-1183;
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: Blaine Williams, Aerospace Engineer,
Los Angles ACO Branch, Compliance & Airworthiness Division, 3960
Paramount Blvd., Lakewood, California 90712; telephone 562-627-5371;
email blaine.williams@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-2020-1183; Project Identifier
2019-SW-008-AD" 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
Blaine Williams, Aerospace Engineer, Los Angeles ACO Branch, Compliance
& Airworthiness Division, 3960 Paramount Blvd., Lakewood, California
90712; telephone 562-627-5371; email blaine.williams@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 2019-0008, dated January 22, 2019
(EASA AD 2019-0008), to correct an unsafe condition for certain Airbus
Helicopters (AH), formerly Eurocopter, Eurocopter France, Aerospatiale,
Model EC 155 B, EC 155 B1, SA 365 N, SA 365 N1, AS 365 N2, and AS 365
N3 helicopters.

This proposed AD was prompted by reports of an in-flight loss of
engine and MGB cowlings. Subsequent investigations revealed that the
MGB cowling attachment fittings failed because of mounting stress in
the MGB front fitting and air intake bulkhead. The FAA is proposing
this AD to address failure of the MGB front fitting and subsequent
detachment of the MGB or engine cowlings. See EASA AD 2019-0008 for
additional background information.

Related Service Information Under 1 CFR Part 51

EASA AD 2019-0008 requires inspecting the MGB front fittings within
110 flight hours after April 14, 2017 (the effective date of EASA AD
2017-0055, dated March 31, 2017). If there is a discrepancy, the EASA
AD requires applicable corrective action(s) before next flight. EASA AD
2019-0008 also requires modification of the MGB fixed cowling
attachments within 660 flight hours or 23 months, whichever occurs
first, after the effective date described in EASA AD 2019-0008.
Accomplishing the modification constitutes a terminating action for the
required inspection.

The FAA also reviewed Airbus Helicopters Alert Service Bulletin
(ASB) No. AS365-53.00.62 and EC155-53A038, each Revision 0 and dated
December 20, 2018 (ASB AS365-53.00.62 and ASB EC155-53A038). ASB AS365-
53.00.62 applies to Model AS365-series helicopters. ASB EC155-53A038
applies to Model EC155-series helicopters. This service information
specifies replacing the front bracket, inspecting for stress of the MGB
fixed cowlings on the radiator bulkhead, and installing an additional
locking system.

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

These products have been approved by the aviation authority of
another country, and are 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 EASA
AD referenced above. The FAA is proposing this AD after evaluating all
the relevant information and determining the unsafe condition described
previously is likely to exist or develop in other products of these
same type designs.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified
in EASA AD 2019-0008, described previously, as incorporated by
reference, except for any differences identified as exceptions in the
regulatory text of this proposed AD and except as discussed under
"Differences Between this Proposed AD and the EASA AD."

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 2019-0008
will be incorporated by reference in the FAA final rule. This proposed
AD would, therefore, require compliance with EASA AD 2019-0008 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 2019-0008 that is required for compliance with EASA AD 2019-
0008 will be available on the internet at https://www.regulations.gov
by searching for and locating Docket No. FAA-2020-1183 after the FAA
final rule is published.

Costs of Compliance

The FAA estimates that this proposed AD affects 19 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.

Inspecting the MGB front fittings would take about 2 work-hours for
an estimated cost of $170 per helicopter and $3,230 for the U.S. fleet.
If required, replacing an MGB front fitting would take about 2 work-
hours and parts would cost about $590 for an estimated total cost of
$760 per fitting. Other repairs could take up to 8 work-hours
(excluding drying time) and parts would cost a minimal amount for an
estimated cost of up to $680 per helicopter.

Modifying the MGB fixed cowling attachments would take about 5
work-hours and parts would cost about $630 for an estimated cost of
$1,055 per helicopter and $20,045 for the U.S. fleet.

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: