DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0512; Project Identifier MCAI-2020-01621-R;
Amendment 39-21627; AD 2021-13-21]
RIN 2120-AA64

Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Leonardo S.p.a. Model AB139, AW139, and AW189 helicopters. This
AD was prompted by a report of the in-flight failure of one of the
three stainless steel external rings bonded to the main rotor
swashplate boot. This AD requires repetitive inspections of these
stainless steel external rings for corrosion, cracks, and the condition
of the adhesive that bonds the rings to the main rotor swashplate boot,
and corrective action if necessary, as specified in a European Union
Aviation Safety Agency (EASA) AD, which is incorporated by reference.
The FAA is issuing this AD to address the unsafe condition on these
products.

DATES: This AD becomes effective July 12, 2021.

The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 12, 2021.

The FAA must receive comments on this AD by August 9, 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 EASA material incorporated by reference (IBR) in this AD,
contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone
+49 221 8999 000; email ADs@easa.europa.eu; internet www.easa.europa.eu
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 the EASA 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 the
EASA material at the FAA, call (817) 222-5110. The EASA material is
also available at https://www.regulations.gov by searching for and
locating Docket No. FAA-2021-0512.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0512; 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 EASA AD, any
comments received, and other information. The street address for Docket
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Darren Gassetto, Aerospace Engineer,
COS Program Management Section, Operational Safety Branch, Compliance &
Airworthiness Division, FAA, 1600 Stewart Ave., Suite 410, Westbury, NY
11590; telephone (516) 228-7323; email Darren.Gassetto@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD 2020-0271, dated December 8, 2020
(EASA AD 2020-0271) (also referred to as the Mandatory Continuing
Airworthiness Information, or the MCAI), to correct an unsafe condition
for Leonardo S.p.A. (formerly Finmeccanica S.p.A, AgustaWestland
S.p.A., Agusta S.p.A.; and AgustaWestland Philadelphia Corporation,
formerly Agusta Aerospace Corporation) Model AB139, AW139, and AW189
helicopters, all serial numbers. Although EASA AD 2020-0271 applies to
Model AB139, AW139, and AW189 helicopters, all serial numbers, this AD
applies to helicopters with an affected part installed instead.

This AD was prompted by a report of the in-flight failure of one of
the three stainless steel external rings bonded to the main rotor
swashplate boot installed on Model AB139 and AW139 helicopters. The
broken ring, under the effects of the centrifugal force, was released
from the main rotor swashplate boot and impacted one tail rotor blade,
causing extensive damage. Investigation revealed that the failure of
the external ring was caused by fatigue initiated by corrosion. A
contributing factor to the external ring failure was disbonding at the
four points where the affected ring was bonded to the main rotor
swashplate boot. Leonardo S.p.a. Model AW189 helicopters have a similar
design, therefore, this model may be subject to the same unsafe
condition revealed on the Model AB139 and AW139 helicopters. Since EASA
AD 2020-0271 was published, there have been two more reports of
discrepant main rotor boots.

The FAA is issuing this AD to address corrosion, cracking, and
damage to the adhesive (e.g., disbonding) of any stainless steel
external ring bonded to the main rotor swashplate boot, which could
result in release of a ring from the main rotor swashplate boot,
resulting in damage to, and reduced control of, the helicopter. See the
EASA AD for additional background information.

Related IBR Material Under 1 CFR Part 51

EASA AD 2020-0271 specifies procedures for repetitive detailed
inspections (DET) of the affected external rings for corrosion
(including superficial oxidation), and cracks, and, depending on
findings, polishing corrosion, and replacing an affected external ring
with a serviceable part. EASA AD 2020-0271 also requires repetitive
inspections for damage of the adhesive (e.g., disbonding) between the
bonding areas of the affected external rings and the main rotor
swashplate boot and re-applying the adhesive if necessary. For certain
helicopters, EASA AD 2020-0271 requires a one-time restoring of the
adhesive between the bonding areas of the affected external rings and
the main rotor swashplate boot. For all helicopters, EASA AD 2020-0271
allows, under certain conditions, (re)installation of an affected part
on a helicopter.

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

These products have been approved by the aviation authority of
another country, and are approved for operation in the United States.
Pursuant to the FAA's bilateral agreement with the State of Design
Authority, the FAA has been notified of the unsafe condition described
in the MCAI referenced above. The FAA is issuing this AD after
evaluating all pertinent information and determining that the unsafe
condition exists and is likely to exist or develop on other products of
these same type designs.

Requirements of This AD

This AD requires accomplishing the actions specified in EASA AD
2020-0271, described previously, as incorporated by reference, except
for any differences identified as exceptions in the regulatory text of
this 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 2020-0271
is incorporated by reference in the FAA final rule. This AD would,
therefore, require compliance with EASA AD 2020-0271 in its entirety,
through that incorporation, except for any differences identified as
exceptions in the regulatory text of this 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 2020-0271 that is
required for compliance with EASA AD 2020-0271 is available on the
internet at https://www.regulations.gov by searching for and locating
Docket No. FAA-2021-0512.

FAA's Justification and Determination of the Effective Date

Section 553(b)(3)(B) of the Administrative Procedure Act (5 U.S.C.
551 et seq.) authorizes agencies to dispense with notice and comment
procedures for rules when the agency, for "good cause" finds that
those procedures are "impracticable, unnecessary, or contrary to the
public interest." Under this section, an agency, upon finding good
cause, may issue a final rule without providing notice and seeking
comment prior to issuance. Further, section 553(d) of the APA
authorizes agencies to make rules effective in less than thirty days,
upon a finding of good cause.

An unsafe condition exists that requires the immediate adoption of
this AD without providing an opportunity for public comments prior to
adoption. The FAA has found that the risk to the flying public
justifies foregoing notice and comment prior to adoption of this rule
because the in-flight failure of a stainless steel external ring bonded
to the main rotor swashplate boot could result in damage to, and
reduced control of, the helicopter. In addition, the compliance time
for the required action is shorter than the time necessary for the
public to comment and for publication of the final rule. Based on the
average utilization rate for the affected Model AB139 and AW139
helicopters, it would take approximately one month for an affected
helicopter to reach 25 hours time-in-service. Therefore, notice and
opportunity for prior public comment are impracticable and contrary to
public interest pursuant to 5 U.S.C. 553(b)(3)(B). In addition, the FAA
finds that good cause exists pursuant to 5 U.S.C. 553(d) for making
this amendment effective in less than 30 days, for the same reasons the
FAA found good cause to forego notice and comment.

Comments Invited

The FAA invites you to send any written relevant data, views, or
arguments about this AD. Send your comments to an address listed under
ADDRESSES. Include "Docket No. FAA-2021-0512; Project Identifier MCAI-
2020-01621-R" at the beginning of your comments. The most helpful
comments reference a specific portion of the AD, 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
AD 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 AD.

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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Darren
Gassetto, Aerospace Engineer, COS Program Management Section,
Operational Safety Branch, Compliance & Airworthiness Division, FAA,
1600 Stewart Ave., Suite 410, Westbury, NY 11590; telephone (516) 228-
7323; email Darren.Gassetto@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.

Regulatory Flexibility Act (RFA)

The requirements of the RFA do not apply when an agency finds good
cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and
comment. Because the FAA has determined that it has good cause to adopt
this rule without notice and comment, RFA analysis is not required.

Costs of Compliance

The FAA estimates that this AD affects 142 helicopters of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

Estimated Costs of On-Condition Actions

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

The FAA determined that this AD would not have federalism
implications under Executive Order 13132. This 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 regulation:

(1) Is not a "significant regulatory action" under Executive
Order 12866, and

(2) Will not affect intrastate aviation in Alaska.

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: