DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0293; Product Identifier 2017-SW-052-AD; Amendment
39-21610; AD 2021-13-05]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
Airbus Helicopters Deutschland GmbH (Airbus Helicopters) Model EC135P1,
EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3
helicopters. This AD requires modifying the tail rotor (T/R) control
installation, a functional test, and corrective actions as necessary.
This AD was prompted by cases of insufficient clearance between a
certain T/R control bearing connection and the helicopter structure,
which were detected on the production line. The FAA is issuing this AD
to address the unsafe condition on these products.

DATES: This AD is effective August 11, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain document listed in this AD as of August 11,
2021.

ADDRESSES: For service information identified in this final rule,
contact Airbus Helicopters, 2701 North 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. Service information that is incorporated by
reference is also available at https://www.regulations.gov
by searching for and locating Docket No. FAA-2019-0293.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2019-0293; 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 final rule, the
European Aviation Safety Agency (now European Union Aviation Safety
Agency) (EASA) AD, any comments received, and other information. The
street address for Docket Operations 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: David Hatfield, Aviation Safety
Engineer, Aircraft Systems Section, Technical Innovation Policy Branch,
FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-
5110; email david.hatfield@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to Airbus Helicopters
Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+,
and EC135T3 helicopters with serial number (S/N) up to and including
1254 (except S/N 1235). The NPRM published in the Federal Register on
April 16, 2021 (86 FR 20089). In the NPRM, the FAA proposed to require
modifying the T/R control within 360 hours time-in-service (TIS) by
installing a Teflon washer and performing a functional test in
accordance with specified portions of Airbus Helicopters Alert Service
Bulletin ASB EC135-67A-031, Revision 0, dated March 30, 2017 (ASB
EC135-67A-031). Based on the results of the functional test, the NPRM
proposed to require making repairs in accordance with FAA-approved
procedures. The NPRM was prompted by EASA AD 2017-0147, dated August
10, 2017 (EASA AD 2017-0147), issued by EASA, which is the Technical
Agent for the Member States of the European Union, to correct an unsafe
condition for Airbus Helicopters Model EC135P1, EC135P2, EC135P2+,
EC135P3, EC135T1, EC135T2, EC135T2+, EC135T3, EC635P2+, EC635P3,
EC635T1, EC635T2+, and EC635T3 helicopters. EASA advises that several
cases of insufficient clearance between a certain T/R bearing
connection and the helicopter structure were detected during
inspections of helicopters on the production line. EASA states that
this condition, if not corrected and in the case of an unglued bearing,
could lead to blockage of the pedal controlling the T/R thrust and loss
of the T/R control. EASA further advises that this could result in a
forced landing with damage to the helicopter and injury to the
occupants.
Accordingly, EASA AD 2017-0147 requires modifying the T/R control
installation by adding a Teflon washer, which reduces the degree of
freedom in case of a drifting bearing at the affected connection. EASA
AD 2017-0147 also requires a functional test for clearance, and
depending on the results, either accomplishing additional corrective
actions or contacting Airbus Helicopters for instructions.

Comments

The FAA received no comments on the NPRM or on the determination of
the costs.

Conclusion

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 reviewed the relevant
data and determined that air safety requires adopting this AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these helicopters.

Related Service Information Under 1 CFR Part 51

The FAA reviewed ASB EC135-67A-031 for Airbus Helicopters Model
EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+,
EC135T3, EC635P2+, EC635P3, EC635T1, EC635T2+, and EC635T3 helicopters.
For S/Ns up to 1254 inclusive, except S/N 1235, this service
information specifies retrofitting a Teflon washer on the T/R controls,
performing a functional test of the modified T/R control installation
to inspect for clearance, and making any necessary adjustments. This
service information advises that S/N 1255 and up will have the Teflon
washer installed in production.
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.

Differences Between This AD and the EASA AD

The EASA AD sets compliance times at 12 months, while this AD
requires compliance within 360 hours TIS. The EASA AD applies to Airbus
Helicopters Model EC635T1, EC635T2+, EC635T3, EC635P2+, and EC635P3
helicopters; this AD does not because these models do not have an FAA
type certificate. The EASA AD requires contacting Airbus Helicopters
for approved repair procedures; this AD requires a repair using FAA-
approved procedures. The EASA AD requires revising the ``aircraft
maintenance program,'' whereas this AD does not because not all U.S.
operators are required to have a maintenance program.

Costs of Compliance

The FAA estimates that this AD affects 331 helicopters of U.S.
registry. Labor rates are estimated at $85 per work-hour. Based on
these numbers, the FAA estimates the following costs to comply with
this AD.
Modifying the T/R control installation and conducting a functional
test takes about 3 work-hours and parts cost about $25 for an estimated
cost of $280 per helicopter and $92,680 for the U.S. fleet.
If required, adjusting the clearance takes about 1 work-hour for an
estimated cost of $85 per helicopter.

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 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) 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 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: