DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0103; Project Identifier MCAI-2020-00604-E]
RIN 2120-AA64

Airworthiness Directives; Pratt & Whitney Canada Corp. Turboshaft
Engines

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 Pratt & Whitney Canada Corp. (P&WC) PW210A and PW210S model
turboshaft engines. This proposed AD was prompted by a report from the
manufacturer that the Automated Damage Tracking System (ADTS) may
under-count the number of cycles accrued by the impeller and the high-
pressure compressor (HPC) rotor. The impeller and HPC rotor are both
life-limited components and exceeding their published life limits could
result in the failure of these components. This proposed AD would
require the use of the manual low-cycle fatigue (LCF) counting method
in place of the ADTS counting method to determine the number of cycles
accrued by the impeller and HPC rotor. 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 April 12,
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 Pratt &
Whitney Canada Corp., 1000 Marie-Victorin, Longueuil, Quebec, J4G 1A1
Canada; phone: (800) 268-8000. You may view this service information at
the FAA, Airworthiness Products Section, Operational Safety Branch,
1200 District Avenue, Burlington, MA 01803. For information on the
availability of this material at the FAA, call (781) 238-7759.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0103; 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
mandatory continuing airworthiness information (MCAI), any comments
received, and other information. The street address for Docket
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aviation Safety
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803;
phone: (781) 238-7146; fax: (781) 238-7199; email:
barbara.caufield@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-2021-0103; Project Identifier
MCAI-2020-00604-E" 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 we receive 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
Barbara Caufield, Aviation Safety Engineer, ECO Branch, FAA, 1200
District Avenue, Burlington, MA 01803. Any commentary that the FAA
receives which is not specifically designated as CBI will be placed in
the public docket for this rulemaking.

Background

Transport Canada Civil Aviation (Transport Canada), which is the
aviation authority for Canada, has issued Transport Canada AD CF-2020-
13, dated April 28, 2020 (referred to after this as "the MCAI"), to
address the unsafe condition on these products. The MCAI states:

The engine manufacturer has discovered that the Automated Damage
Tracking System (ADTS) may under-count the number of cycles accrued
by the impeller and the High Pressure (HP) compressor rotor. The
impeller and HP compressor rotor are both life limited components
and exceeding their published life limits could result in the
failure of these components.

Failure of the impeller or HP compressor rotor could result in
the uncontained release of the impeller or the HP compressor rotor,
and subsequently could result in damage to the engine, damage to the
helicopter, and loss of control of the helicopter.

This [Transport Canada] AD mandates the use of the Manual Low
Cycle Fatigue (LCF) Counting method to ensure that the impeller and
HP compressor rotor do not exceed their published life limits.

You may obtain further information by examining the MCAI in the AD
docket at https://www.regulations.gov by searching for and locating
Docket No. FAA-2021-0103.

FAA's Determination

This product has been approved by the aviation authority of Canada
and is approved for operation in the United States. Pursuant to our
bilateral agreement with Canada, Transport Canada has notified the FAA
of the unsafe condition described in the MCAI and service information.
The FAA is issuing this AD because the agency evaluated all the
relevant information provided by Transport Canada and determined the
unsafe condition described previously is likely to exist or develop in
other products of the same type design.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Pratt & Whitney Canada Corp. Alert Service
Bulletin (ASB) No. PW210-72-A57142, Revision No. 1, dated March 26,
2020 (ASB No. PW210-72-A57142); and Pratt & Whitney Canada Corp. ASB
No. PW210-72-A57143, Revision No. 1, dated March 26, 2020 (ASB No.
PW210-72-A57143). ASB No. PW210-72-A57142 specifies procedures for
calculating the correct, current LCF cycle count for the impeller and
HPC rotor on PW210A model turboshaft engines. ASB No. PW210-72-A57143
specifies procedures for calculating the correct, current LCF cycle
count for the impeller and HPC rotor installed on PW210S model
turboshaft engines.

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 reviewed Pratt & Whitney Canada Corp. Task 00-00-00-860-801
and Task 00-00-00-860-803 of Pratt & Whitney Canada Corp. Engine
Maintenance Manual (EMM), Manual Part No. 30L2392, Airworthiness
Limitations Section (ALS), both at Revision 13, dated September 28,
2020.

Pratt & Whitney Canada Corp. Task 00-00-00-860-801 of Pratt &
Whitney Canada Corp. EMM, Manual Part No. 30L2392, identifies the LCF
life limits for the impeller and HPC rotor. Pratt & Whitney Canada
Corp. Task 00-00-00-860-803 of Pratt & Whitney Canada Corp. EMM, Manual
Part No. 30L2392, specifies procedures for manually calculating the
correct, current LCF cycle count for the impeller and HPC rotor and
provides the formula for manually calculating the accumulated total
cycles for the impeller and HPC rotor.

Proposed AD Requirements in This NPRM

This proposed AD would require the use of the manual LCF counting
method in place of the ADTS counting method to determine the number of
cycles accrued by the impeller and HPC rotor.

Interim Action

The FAA considers that this proposed AD would be an interim action.
If final action is later identified, the FAA might consider additional
rulemaking.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 66 engines installed on helicopters of U.S. registry.

The FAA estimates the following costs to comply with this proposed
AD:

Estimated Costs
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Action Labor cost Parts cost Cost per product Cost on U.S. operators
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Manually calculate LCF cycles. 1 work-hour x $85 per hour = $85 $0 $85 $5,610
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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: