DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA 2022-0460; Project Identifier AD-2021-00824-R]
RIN 2120-AA64

Airworthiness Directives; Bell Textron Inc., Helicopters and
Various Restricted Category 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 Bell Textron Inc., Model 204B, 205A, 205A-1, 205B, 210, 212, 412,
412CF, and 412EP helicopters and various restricted category
helicopters. This proposed AD was prompted by reports of cracks found
on the main transmission support case. This proposed AD would require
repetitive inspections of the main transmission housing assembly for
cracks, pitting, and corrosion and depending on the results, corrective
action. 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 May 31,
2022.

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 Bell Helicopter service information identified in this AD,
contact Bell Textron, Inc., P.O. Box 482, Fort Worth, TX, 76101, United
States; phone (450) 437-2862 or (800) 363-8023; fax (450) 433-0272;
email productsupport@bellflight.com; or at https://www.bellflight.com/support/contact-
support. You may purchase the ASTM International
standard from ASTM International at https://www.astm.org/. 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.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA 2022-0460; 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.

FOR FURTHER INFORMATION CONTACT: Hye Yoon Jang, Aerospace Engineer,
Delegation Oversight Section, DSCO Branch, Compliance & Airworthiness
Division, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone
(817) 222-5190; email hye.yoon.jang@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 2022-0460; Project Identifier
AD-2021-00824-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
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 NPRM. Submissions containing CBI should be sent to Hye
Yoon Jang, Aerospace Engineer, Delegation Oversight Section, DSCO
Branch, Compliance & Airworthiness Division, FAA, 10101 Hillwood Pkwy.,
Fort Worth, TX 76177; telephone (817) 222-5190; email
hye.yoon.jang@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 Bell Textron Inc., Model
204B, 205A, 205A-1, 205B, 210, 212, 412, 412CF, and 412EP helicopters
and the following restricted category helicopters:
Model HH-1K helicopters; current type certificate holders
include but are not limited to Rotorcraft Development Corporation;
Southwest Florida Aviation International, Inc., Model
SW205A-1 helicopters;
Model TH-1F helicopters; current type certificate holders
include but are not limited to Robinson Air Crane Inc.; Rotorcraft
Development Corporation; and Tamarack Helicopters, Inc.;
Model TH-1L helicopters; current type certificate holders
include but are not limited to Bell Textron Inc.; Overseas Aircraft
Support, Inc. (type certificate previously held by JTBAM, Inc.); and
Rotorcraft Development Corporation;
Model UH-1A helicopters; current type certificate holders
include but are not limited to Richards Heavylift Helo, Inc.;
Model UH-1B helicopters; current type certificate holders
include but are not limited to International Helicopters, Inc.;
Overseas Aircraft Support, Inc.; Red Tail Flying Services, LLC;
Richards Heavylift Helo, Inc.; Rotorcraft Development Corporation;
Southwest Florida Aviation International, Inc. (helicopters with an
SW204 or SW204HP designation are Southwest Florida Aviation
International, Inc., Model UH-1B helicopters); and WSH, LLC (type
certificate previously held by San Joaquin Helicopters);
Model UH-1E helicopters; current type certificate holders
include but are not limited to Bell Textron Inc.; Overseas Aircraft
Support, Inc.; Rotorcraft Development Corporation; Smith Helicopters;
and West Coast Fabrications;
Model UH-1F helicopters; current type certificate holders
include but are not limited to AST, Inc.; California Department of
Forestry; Robinson Air Crane, Inc.; Rotorcraft Development Corporation;
and Tamarack Helicopters, Inc.;
Model UH-1H helicopters; current type certificate holders
include but are not limited to Arrow Falcon Exporters Inc.; Global
Helicopter Technology, Inc.; Hagglund Helicopters, LLC; JJASPP
Engineering Services, LLC; Northwest Rotorcraft, LLC; Overseas Aircraft
Support, Inc.; Richards Heavylift Helo, Inc.; Rotorcraft Development
Corporation; Southwest Florida Aviation International, Inc.
(helicopters with an SW205 designation are Southwest Florida Aviation
International, Inc., Model UH-1H helicopters); and Tamarack
Helicopters, Inc.;
Model UH-1L helicopters; current type certificate holders
include but are not limited to Bell Textron Inc.; Overseas Aircraft
Support, Inc.; and Rotorcraft Development Corporation; and
Model UH-1P helicopters; current type certificate holders
include but are not limited to Robinson Air Crane, Inc.; and Rotorcraft
Development Corporation.
This proposed AD would require repetitive inspections of the main
transmission housing assembly. This proposed AD was prompted by reports
of main transmission support cases found cracked at one of the lateral
mounts. This condition, if not addressed, could result in cracking at
the upper or lower surfaces of the lateral mounts, loss of load
carrying capabilities of the main transmission, 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.

Other Related Service Information

The FAA reviewed Fluorescent Penetrant Inspection Method (ASTM
E1417) of Chapter 6--Non-Destructive Inspection, of Bell Helicopter,
Standard Practices Manual BHT-ALL-SPM, Revision 8, dated August 30,
2021, and ASTM International Standard Practice for Liquid Penetrant
Testing E1417/E1417M-21, dated September 1, 2021 (ASTM E1417). This
service information specifies procedures for the fluorescent penetrant
inspection.

Proposed AD Requirements in This NPRM

This proposed AD would require, within 3,000 hours time-in-service
(TIS) accumulated by the main transmission after the effective date of
this proposed AD, and thereafter at intervals not to exceed 3,000 hours
TIS accumulated by the main transmission, removing certain screws and
washers and visually inspecting the upper and lower transmission
support case lateral mount screws for corrosion and thread damage,
washers for corrosion and pitting, bushings for corrosion and pitting,
and lateral mount surfaces for corrosion and mechanical damage such as
any crack or pitting. If there is any corrosion, thread damage, or
mechanical damage, this proposed AD would require removing the affected
parts from service before further flight.
This proposed AD would also require repetitive fluorescent
penetrant inspections (FPIs) of all surfaces of the main transmission
support case lateral mounts for a crack. For helicopters with a main
transmission that has accumulated 6,000 or more total hours TIS, the
initial FPI would be required before further flight after the effective
date of this AD. For helicopters with a main transmission that has
accumulated less than 6,000 total hours TIS, the initial FPI would be
required before the main transmission accumulates 6,000 total hours
TIS. For all helicopters, following the initial FPI, this proposed AD
would require performing an FPI at intervals not to exceed 6,000 hours
TIS accumulated by the main transmission. If there is any crack, this
proposed AD would require removing the main transmission support case
from service before further flight.

Costs of Compliance

The FAA estimates that this proposed AD would affect up to 621
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.
Inspecting the main transmission mount assembly would take about 1
work-hour, for an estimated cost of $85 per helicopter and $52,785 for
the U.S. fleet, per inspection cycle.
Inspecting the main transmission support case lateral mounts by
fluorescent penetrant method would take about 1 work-hour for an
estimated cost of $85 per helicopter, and $52,785 for the U.S. fleet,
per inspection cycle.
If required, replacing the transmission support case assembly
hardware parts including 8 washers, 8 screws, and 4 bushings would take
about 1 work-hour and parts would cost up to $100 per part for an
estimated cost of up to $2,000 per helicopter.
If required, replacing the main transmission support case assembly
would take up to 60 work-hours and parts would cost up to $54,501 for
an estimated cost of up to $59,601 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: