DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0380; Project Identifier MCAI-2020-01683-R;
Amendment 39-21672; AD 2021-16-10]
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
certain Airbus Helicopters Deutschland GmbH Model EC135P1, EC135P2,
EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters.
This AD was prompted by a report that geometrical non-conformities were
found in the root section of the tail rotor blade (TRB). This AD
requires a one-time inspection (dimensional check) of the TRB for
conformity and, depending on the findings, replacement of certain
affected parts, as specified in a European Union Aviation Safety Agency
(EASA) AD, which is incorporated by reference. This AD also prohibits
rework, repair, or modification of affected parts in the affected area
of the TRB assembly root. The FAA is issuing this AD to address the
unsafe condition on these products.

DATES: This AD is effective October 13, 2021.

The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of October 13,
2021.

ADDRESSES: For material incorporated by reference (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 IBR 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-2021-0380.

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-2021-
0380; 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, any comments received, and other information. The
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: Andrea Jimenez, Aerospace Engineer,
COS Program Management Section, Operational Safety Branch, Compliance &
Airworthiness Division, FAA, 1600 Stewart Ave., Mail Stop: Room 410,
Westbury, NY 11590; telephone 516-228-7330; email
andrea.jimenez@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD 2020-0282, dated December 17, 2020
(EASA AD 2020-0282) (also referred to as the Mandatory Continuing
Airworthiness Information, or the MCAI), to correct an unsafe condition
for Airbus Helicopters Deutschland GmbH Model EC135 P1, EC135 P2, EC135
P2+, EC135 P3, EC135 T1, EC135 T2, EC135 T2+, EC135 T3, EC635 P2+,
EC635 P3, EC635 T1, EC635 T2+, and EC635 T3 helicopters, all variants,
all serial numbers. Model EC635 P2+, EC635 P3, EC635 T1, EC635 T2+, and
EC635 T3 helicopters are not certificated by the FAA and are not
included on the U.S. type certificate data sheet, except where the U.S.
type certificate data sheet explains that the Model EC635T2+ helicopter
having serial number 0858 was converted from Model EC635T2+ to Model
EC135T2+. This AD, therefore, does not include Model EC635 P2+, EC635
P3, EC635 T1, EC635 T2+, and EC635 T3 helicopters in the applicability.

Furthermore, although EASA AD 2020-0282 applies to all Model EC135
P1, EC135 P2, EC135 P2+, EC135 P3, EC135 T1, EC135 T2, EC135 T2+, and
EC135 T3 helicopters, this AD applies to helicopters with an affected
part installed instead.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain Airbus
Helicopters Deutschland GmbH Model EC135P1, EC135P2, EC135P2+, EC135P3,
EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters. The NPRM published
in the Federal Register on June 1, 2021 (86 FR 29216). The NPRM was
prompted by a report that during an investigation related to an
accident on an Airbus Helicopters Model EC130B4 helicopter, geometrical
non-conformities were observed in the TRB root section. EASA issued AD
2020-0187, dated August 21, 2020, to address this issue on Model
EC130B4 and EC130T2 helicopters and the FAA issued corresponding AD
2021-10-25, Amendment 39-21558 (86 FR 29176, June 1, 2021). The Airbus
Helicopters Deutschland GmbH Model EC135P1, EC135P2, EC135P2+, EC135P3,
EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters have a similar
design and production requirements to the affected Model EC130B4
helicopter, and an inspection of the affected parts detected
geometrical non-conformities in some instances. The NPRM proposed to
require a one-time inspection (dimensional check) of the TRB for
conformity and, depending on the findings, replacement of certain
affected parts, as specified in EASA AD 2020-0282. The NPRM also
proposed to prohibit rework, repair, or modification of affected parts
in the affected area of the TRB assembly root.

The FAA is issuing this AD to address geometrical non-conformities
in the TRB root section, which could lead to crack initiation and
consequent blade failure, resulting in loss of control of the
helicopter. See the MCAI for additional background information.

Comments

The FAA gave the public the opportunity to participate in
developing this final rule. The FAA received no comments on the NPRM or
on the determination of the cost to the public.

Conclusion

The FAA reviewed the relevant data and determined that air safety
and the public interest require adopting this final rule as proposed,
except for minor editorial changes. The FAA has determined that these
minor changes:

Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and

Do not add any additional burden upon the public than was
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

EASA AD 2020-0282 requires a one-time inspection (dimensional
check) to verify TRB conformity, and, depending on findings,
replacement of each affected part classified as Category B (non-
compliant TRB assembly). EASA AD 2020-0282 also prohibits rework,
repair, or modification of affected parts in the critical section
(affected area of the TRB assembly root).

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.

Costs of Compliance

The FAA estimates that this AD affects 341 helicopters of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

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. The FAA has no way of determining the number of
helicopters that might need these on-condition actions:

Estimated Costs of On-Condition Actions

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

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.

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: