DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0829; Project Identifier MCAI-2021-00189-R;
Amendment 39-21829; AD 2021-24-08]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2021-04-
21, which applies to certain Airbus Helicopters Model EC120B
helicopters. AD 2021-04-21 required an inspection of the attachment
bolts of the main rotor (MR) hub scissors assembly for discrepancies
and repair if necessary; part marking of the attachment bolts of the MR
hub scissors assembly; and repetitive inspections of the part marking
of the attachment bolts, and repair if necessary. This AD continues to
require the actions in AD 2021-04-21; and also requires part marking of
the washer, scissor branch, and mast ring of the corresponding nut
side, and repetitive inspections of the additional part markings and
repair if necessary; as specified in a European Union Aviation Safety Agency
(EASA) AD, which is incorporated by reference. This AD was prompted by a report of
broken and bent attachment bolts of the MR hub scissors assembly and a
determination that additional part markings of the washer, scissor
branch, and mast ring of the corresponding nut side, and repetitive
inspections of those part markings, are necessary to detect any
rotation. The FAA is issuing this AD to address the unsafe condition on
these products.

DATES: This AD is effective January 14, 2022.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of January 14,
2022.

ADDRESSES: 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 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-2021-0829.

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-
0829; 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: Hal Jensen, Aerospace Engineer,
Operational Safety Branch, Compliance & Airworthiness Division, FAA,
950 L'Enfant Plaza N SW, Washington, DC 20024; phone: (202) 267-9167;
email: hal.jensen@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD 2021-0046, dated February 12, 2021
(EASA AD 2021-0046) (also referred to as the Mandatory Continuing
Airworthiness Information, or the MCAI), to correct an unsafe condition
for all Airbus Helicopters Model EC120B helicopters. Although EASA AD
2021-0046 applies to all Model EC120B 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 to supersede AD 2021-04-21, Amendment 39-21443 (86 FR
17278, April 2, 2021) (AD 2021-04-21). AD 2021-04-21 applied to certain
Airbus Helicopters Model EC120B helicopters. The NPRM published in the
Federal Register on September 23, 2021 (86 FR 52859). The NPRM was
prompted by a report of broken and bent attachment bolts of the MR hub
scissors assembly and a determination that additional part markings of
the washer, scissor branch, and mast ring of the corresponding nut
side, and repetitive inspections of those part markings, are necessary
to detect any rotation. The NPRM proposed to continue to require the
actions in AD 2021-04-21, as specified in an EASA AD. The NPRM also
proposed to require part marking of the washer, scissor branch, and
mast ring of the corresponding nut side, and repetitive inspections of
the additional part markings and repair if necessary, as specified in
an EASA AD.
The FAA is issuing this AD to address broken and bent attachment
bolts of the MR hub scissors assembly, which could lead to detachment
of a MR hub scissors attachment bolt, possibly resulting in complete
loss of control of the helicopter. See the MCAI for additional
background information.

Discussion of Final Airworthiness Directive

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 2021-0046 specifies procedures for an inspection of the
attachment bolts of the MR hub scissors assembly for discrepancies
(discrepancies include corrosion, fretting, wear, cracking, bolt play,
and bolt tightening torque) and repair if necessary; part marking of
the washer, scissor branch, and mast ring of the attachment bolts and
corresponding nut side of the MR hub scissors assembly; and repetitive
inspections, after part marking, for discrepancies, and repair if
necessary. The inspections of the attachment bolts of the MR hub
assembly include checking the play and torque of the scissors
attachment bolts and making sure that there are no hard spots in the
scissors link hinge.
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 89 helicopters of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

The FAA estimates that it would take about 1 hour per product to
comply with the reporting requirement in this AD. The average labor
rate is $85 per hour. Based on these figures, the FAA estimates the
cost of reporting on U.S. operators to be $7,565, 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. The FAA has no way of determining the number of
helicopters that might need these on-condition actions:

On-Condition Costs

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 AD is 2120-
0056. The paperwork cost associated with this 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 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 Pkwy., 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

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:

a. Removing Airworthiness Directive (AD) 2021-04-21, Amendment 39-21443
(86 FR 17278, April 2, 2021); and

b. Adding the following new AD: