DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0384; Product Identifier 2017-SW-061-AD; Amendment
39-19401; AD 2018-19-01]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for Airbus
Helicopters Model AS-365N2, AS 365 N3, EC 155B, EC155B1, SA-365N1, and
SA-366G1 helicopters. This AD requires repetitive inspections of the
aft fuselage outer skin. This AD was prompted by several reports of aft
fuselage outer skin disbonding. The actions of this AD are intended to
address an unsafe condition on these products.

DATES: This AD is effective October 22, 2018.
The Director of the Federal Register approved the incorporation by
reference of certain documents listed in this AD as of October 22,
2018.

ADDRESSES: For service information identified in this final 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 http://www.helicopters.airbus.com/website/en/ref/Technical-
Support_73.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. 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. It is also available on the internet at http://www.regulations
.gov by searching for and locating Docket No. FAA-2018- 0384.

Examining the AD Docket

You may examine the AD docket on the internet at http://www.regulations.gov
by searching for and locating Docket No. FAA-2018-
0384; 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 AD, the European Aviation Safety Agency (EASA) AD, any
incorporated-by-reference service information, the economic evaluation,
any comments received, and other information. The street address for
Docket Operations (phone: 800-647-5527) is U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

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:

Discussion

On May 9, 2018, at 83 FR 21194, the Federal Register published our
notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR
part 39 by adding an AD that would apply to Airbus Helicopters Model
AS-365N2, AS 365 N3, EC 155B, EC155B1, SA-365N1, and SA-366G1
helicopters.
The NPRM proposed to require a repetitive tap inspection of the aft
fuselage outer skin for disbonding. Depending on the inspection
results, the NPRM proposed to require reducing the compliance time
interval of the tap inspections or repairing or replacing the panel to
terminate the shorter compliance time interval. The NPRM also proposed
to require a repetitive cleaning of the aft fuselage outer skin to
visually inspect for distortion, wrinkling, and corrosion. Depending on
the visual inspection results, the NPRM proposed to require an
additional tap inspection of the area. The proposed
requirements were intended to detect disbonding of the aft fuselage
outer skin, which could result in loss of aft fuselage structural
integrity and subsequent loss of control of the helicopter.
The NPRM was prompted by AD No. 2017-0165, dated September 5, 2017
(EASA AD 2017-0165), issued by EASA, which is the Technical Agent for
the Member States of the European Union, to correct an unsafe condition
for the Airbus Helicopters Model SA 365 N1, AS 365 N2, AS 365 N3, SA
366 G1, EC 155 B and EC 155 B1 helicopters. EASA advises of several
reports of aft fuselage (baggage compartment area) outer skin
disbonding found during a 600-hour inspection. EASA advises that most
of the reports of disbonding occurred on Model EC 155 helicopters and
may occur in the same area on Model AS 365, SA 365, and SA 366
helicopters due to design similarity. According to EASA, the cause of
the disbonding has not yet been determined and the investigation is
continuing. Airbus Helicopters states possible causes that are being
considered include exhaust gas heat from the exhaust pipes and
environmental conditions. EASA states that this condition, if not
detected and corrected, could reduce the structural integrity of the
aft fuselage, possibly affecting safe flight and landing.
To address this unsafe condition, EASA AD 2017-0165 requires a
repetitive tap inspection of the aft fuselage outer skin for
disbonding, a repetitive visual inspection of the aft fuselage outer
skin for distortion, wrinkling, and corrosion, and contacting Airbus
Helicopters if there is any disbonding.

Comments

We gave the public the opportunity to participate in developing
this AD, but we did not receive any comments on the NPRM.

FAA's Determination

These helicopters have been approved by the aviation authority of
France and are approved for operation in the United States. Pursuant to
our bilateral agreement with France, EASA, its technical
representative, has notified us of the unsafe condition described in
the EASA AD. We are issuing this AD because we evaluated all
information provided by EASA and determined the unsafe condition exists
and is likely to exist or develop on other helicopters of these same
type designs and that air safety and the public interest require
adopting the AD requirements as proposed.

Interim Action

We consider this AD to be an interim action. If final action is
later identified, we might consider further rulemaking then.

Differences Between This AD and the EASA AD

If there is disbonding within the allowable limit, the EASA AD
specifies reporting the inspection results to Airbus Helicopters,
whereas this AD does not. If there is disbonding that exceeds the
allowable limit, the EASA AD specifies contacting Airbus Helicopters
for approved skin panel repair or replacement instructions, whereas
this AD requires repairing or replacing the panel instead.

Related Service Information Under 1 CFR Part 51

We reviewed Airbus Helicopters Alert Service Bulletin (ASB) No.
AS365-05.00.77 for Model AS365 N, N1, N2, and N3 and non-FAA-
certificated Model AS365 F, Fs, Fi, K, and K2 helicopters; ASB No.
SA366-05.48 for Model SA366 G1 and non-FAA-certificated Model SA366 GA
helicopters; and ASB No. EC155-05A033 for Model EC155 B and B1
helicopters, all Revision 0 and all dated July 21, 2017. This service
information specifies repetitive tap and visual inspections between aft
fuselage outer skin frames X4630 and X6630 and defines the allowable
limit of disbonding for this area. If there is distortion, wrinkling,
or corrosion, this service information specifies performing a tap
inspection. If there is disbonding within the allowable limit, this
service information specifies reporting the inspection results to
Airbus Helicopters and performing the recurring tap inspection at a
shorter compliance time interval. If there is disbonding that exceeds
the allowable limit, this service information specifies contacting
Airbus Helicopters for repair before further flight.
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.

Costs of Compliance

We estimate that this AD affects 46 helicopters of U.S. Registry.
We estimate that operators may incur the following costs in order to
comply with this AD.
Tap inspecting the aft fuselage outer skin takes about 3 work-hours
for an estimated cost of $255 per helicopter and $11,730 for the U.S.
fleet per inspection cycle. Visually inspecting the aft fuselage outer
skin takes about 0.3 work-hour for an estimated cost of $26 per
helicopter and $1,196 for the U.S. fleet per inspection cycle.
Repairing a panel takes about 5 work-hours and parts cost about $500
for an estimated cost of $925. Replacing a panel takes about 10 work-
hours and parts cost about $20,000 for an estimated cost of $20,850.

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.
We are 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 helicopters identified in this
rulemaking action.

Regulatory Findings

This AD will not have federalism implications under Executive Order
13132. This AD will 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 that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866;
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979);
(3) Will not affect intrastate aviation in Alaska to the extent
that it justifies making a regulatory distinction; and
(4) 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.
We prepared an economic evaluation of the estimated costs to comply
with this 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.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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):