DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1891; Project Identifier AD-2023-00612-R]
RIN 2120-AA64

Airworthiness Directives; Centerpointe Aerospace Inc. 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 all Centerpointe Aerospace Inc. (Centerpointe) Model S-58BT, S-
58DT, S-58ET, S-58FT, S-58HT, and S-58JT helicopters. This proposed AD
was prompted by an indication of a crack on the angle gearbox mount
(AGBM). This proposed AD would require repetitively performing a
fluorescent penetrant inspection (FPI) and depending on the results,
removing the AGBM from service. 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 November
17, 2023.

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 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.
AD Docket: You may examine the AD docket at regulations.gov by
searching for and locating Docket No. FAA-2023-1891; 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, any comments
received, and other information. The street address for Docket
Operations is listed above.
Material Incorporated by Reference:
For Centerpointe service information identified in this
NPRM, contact Centerpointe Aerospace Inc. at 279 Blackland Road, Fate,
TX 75189; (972) 636-9601; email Operations@avnresources.com; https://www.californiahelicopter.com.
You may view this service information at the FAA, 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.

FOR FURTHER INFORMATION CONTACT: Jacob Fitch, Aviation Safety Engineer,
FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; phone: (817) 222-4130;
email: jacob.fitch@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under ADDRESSES. Include ``Docket No. FAA-2023-1891; Project Identifier
AD-2023-00612-R'' 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
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 NPRM. Submissions containing CBI should be sent to Jacob
Fitch, Aviation Safety Engineer, FAA, 10101 Hillwood Pkwy., Fort Worth,
TX 76177; phone: (817) 222-4130; email: jacob.fitch@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

The FAA proposes to adopt a new AD for all Centerpointe Model S-
58BT, S-58DT, S-58ET, S-58FT, S-58HT, and S-58JT helicopters. During a
preflight inspection, fatigue cracking was found on a Model S-58BT
helicopter in the angle supports and cross-members forming the edges of
the AGBM. Due to their similarity to the Model S-58BT helicopter, the
FAA has determined that Centerpointe Model S-58DT, S-58ET, S-58FT, S-
58HT, and S-58JT helicopters are also affected by the same unsafe
condition. This condition, if not addressed, could result in loss of
the angle gearbox, resulting in loss of main rotor drive and subsequent
loss of control of the helicopter.

FAA's Determination

The FAA is issuing this NPRM after determining that the unsafe
condition described previously is likely to exist or develop on other
products of the same type design.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Centerpointe Aerospace Service Bulletin No. 58B75,
dated April 26, 2023. This service information specifies procedures for
repetitively performing an FPI and reporting the results to the
manufacturer. 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 ADDRESSES.

Proposed AD Requirements in This NPRM

This proposed AD would require repetitive FPIs of the AGBM for a
crack, as specified in the service information already described,
except as discussed under ``Differences Between this Proposed AD and
the Service Information.'' This proposed AD would also require removing
any cracked AGBM from service before further flight.

Differences Between This Proposed AD and the Service Information

Where the service information specifies that the initial FPI be
performed within 120 days after receipt of the service information,
this proposed AD would require the initial FPI to be performed within
250 hours time-in-service. The service information specifies reporting
the results of the FPI to the manufacturer, whereas this proposed AD
would not.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 14 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 proposed AD.
Performing an FPI of the AGBM would take about 5 work-hours and
parts cost $150 for an estimated cost of $575 per helicopter, and
$8,050 for the U.S. fleet, per inspection.
If necessary, replacing an AGBM would take about 41 work-hours and
the parts cost would be $30,000 for an estimated cost of $33,485 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 products identified in this rulemaking action.

Regulatory Findings

The 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 above, I certify this proposed
regulation:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(2) Would not affect intrastate aviation in Alaska, and
(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: