DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0574; Project Identifier 2019-SW-073-AD]
RIN 2120-AA64

Airworthiness Directives; Helicopteres Guimbal
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Helicopteres Guimbal Model CABRI G2
helicopters. This proposed AD was prompted by a report that,
during scheduled maintenance on two helicopters, cracks were found on a
certain main rotor (MR) non-rotating scissor link. This proposed AD
would require replacing an affected MR non-rotating scissor link with a
serviceable part. The FAA is proposing this AD to address the unsafe
condition on these products.

DATES: The FAA must receive comments on this proposed AD by August 23, 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 service information identified in this NPRM, contact
Helicopteres Guimbal, 1070, rue du Lieutenant Parayre,
A[eacute]rodrome d'Aix-en-Provence, 13290 Les Milles, France; telephone
33-04-42-39-10-88; email support@guimbal.com; or at https://www.guimbal.com.

You may view this service information 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. Service information
that is incorporated by reference is also available at https://www.regulations.gov
by searching for and locating Docket No. FAA-2021-
0574.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0574; 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 NPRM, the European
Union Aviation Safety Agency (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:

Comments Invited

The FAA invites you to send any written data, views, or arguments
about this proposal. Send your comments to an address listed under
ADDRESSES. Include "Docket No. FAA-2021-0574; Project Identifier 2019-
SW-073-AD" at the beginning of your comments. The most helpful
comments reference a specific portion of the proposal, 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 proposal 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 NPRM.

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 NPRM 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 NPRM, 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 which is not specifically designated as CBI will be placed in
the public docket for this rulemaking.

Background

EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD 2019-0186, dated July 30, 2019 (EASA
AD 2019-0186), to correct an unsafe condition for
Helicopteres Guimbal Model CABRI G2 helicopters, all
manufacturer serial numbers. EASA advises that, during scheduled
maintenance on two helicopters, cracks were found on the MR non-
rotating scissor link, part number (P/N) G41-10-200. The suspected root
cause for the cracking is corrosion due to stress induced by the
mounting of the metal bushings inside the lug hole. To address this
issue the manufacturer modified the design of the MR non-rotating
scissor link to reinforce the lugs and replace the metal bushings with
plastic bushings. Cracking of a MR non-rotating scissor link, if not
addressed, could result in failure of that scissor link, resulting in
reduced control of the helicopter.

Accordingly, EASA AD 2019-0186 requires replacement of affected MR
non-rotating scissor links with serviceable parts.

FAA's Determination

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 is issuing this AD after
evaluating all known relevant information and determining that the
unsafe condition described previously is likely to exist or develop on
other helicopters of the same type design.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Guimbal Service Bulletin SB 15-015, Revision C,
dated August 27, 2019. This service information specifies procedures
for, among other actions, modifying the helicopter by replacing the MR
non-rotating scissor link, P/N G41-10-200, with a serviceable part, P/N
G41-10-201 (by installing scissor link assembly, P/N G41-12-100, which
includes MR non-rotating scissor link, P/N G41-10-201) and torqueing
the bolts. 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.

Other Related Service Information

The FAA also reviewed Guimbal Service Bulletin SB 15-015, Revision
A, dated July 20, 2015 (SB 15-015, Revision A); and SB 15-015, Revision
B, dated July 12, 2019 (SB 15-015, Revision B). SB 15-015, Revision A,
describes procedures for replacing a MR
non-rotating scissor link, P/N G41-10-200, with P/N G41-12-100, which
has a new, improved design. Service Bulletin SB 15-015, Revision B,
describes the same procedures as SB 15-015, Revision A, and includes a
revised compliance time, an updated Situation section, and added an
action.

Proposed AD Requirements in This NPRM

This proposed AD would require accomplishing the actions specified
in the service information already described.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 32 helicopters of U.S. registry. The FAA estimates the following
costs to comply with this proposed AD:

Estimated Costs for Required 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 FAA determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed 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, I certify that this proposed regulation:

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

(2) Would not affect intrastate aviation in Alaska.

(3) Would 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 Proposed Amendment

Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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: