[Federal Register Volume 88, Number 15 (Tuesday, January 24, 2023)]
[Proposed Rules]
[Pages 4111-4114]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-01148]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-0022; Project Identifier MCAI-2022-00564-E]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Canada Corporation 
Turboprop 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 certain Pratt & Whitney Canada Corporation (P&WC) PW308A and PW308C 
model turbofan engines. This proposed AD was prompted by a 
manufacturer's design review which identified that the combustion 
chamber outer case (CCOC) to rear compressor case (RCC) flange bolt low 
cycle fatigue life was inadequate and that those flange bolts may 
develop cracks resulting in flange bolt fracture. This proposed AD 
would require replacing all CCOC flange bolts and modifying the CCOC 
and inner bypass ducts. This proposed AD would also prohibit 
installation of certain flange bolts on any affected engine, as 
specified in a Transport Canada AD, which is proposed for incorporation 
by reference (IBR). The FAA is proposing this AD to address the unsafe 
condition on these products.

DATES: The FAA must receive comments on this NPRM by March 10, 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 under 
Docket No. FAA-2023-0022; 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

[[Page 4112]]

continuing airworthiness information (MCAI), any comments received, and 
other information. The street address for Docket Operations is listed 
above.
    Material Incorporated by Reference:
    For material that is proposed for IBR in this AD, contact Transport 
Canada, Transport Canada National Aircraft Certification, 159 Cleopatra 
Drive, Nepean, Ontario K1A 0N5, Canada; phone: (888) 663-3639; email: 
[email protected]. You may find this material on the Transport Canada 
website at tc.canada.ca/en/aviation.
     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 (817) 222-5110.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: (781) 238-7146; email: [email protected].

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-2023-0022; Project Identifier 
MCAI-2022-00564-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 
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 
Barbara Caufield, Aviation Safety Engineer, ECO Branch, FAA, 1200 
District Avenue, Burlington, MA 01803; phone: (781) 238-7146; email: 
[email protected]. 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, which is the aviation authority for Canada, has 
issued Transport Canada AD CF-2022-22, dated April 22, 2022 (referred 
to after this as ``the MCAI''), to correct an unsafe condition on P&WC 
PW308A model turbofan engines with build specification (BS) BS935 and 
BS1249, serial numbers PCE-CE0180 and prior, and PW308C model turbofan 
engines with BS1047 and BS1238, serial numbers PCE-CF0967 and prior. 
The MCAI states that during a design review, the manufacturer 
identified that the existing low cycle fatigue life of the flange bolts 
that secure the CCOC and the RCC is inadequate. As of May 6, 2022 (the 
effective date of Transport Canada AD CF-2022-22), there have been no 
reports of cracked flange bolts, however the MCAI states there is 
potential that cracks could develop on the flange bolt which could lead 
to fracture of the bolt. The MCAI also states that to address the 
potential cracking issue, P&WC introduced redesigned flange bolts made 
of an improved fatigue resistant material. P&WC also introduced revised 
procedures to modify the CCOC and the inner bypass duct flange with 
chamfers to reverse the installation direction of the flange bolts. The 
MCAI specifies installation of the redesigned bolt configuration, 
modifications to the COCC and inner bypass duct, and specifies an 
installation prohibition for flange bolts with part numbers MS9698-08 
or MS9698-09 on the affected engines. The FAA is proposing this AD to 
prevent cracking and fracture of the flange bolts which may result in 
flange separation or case rupture, damage to the engine and damage to 
the airplane.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2023-0022.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Transport Canada AD CF-2022-22, which specifies 
instructions for replacing certain CCOC flange bolts and modifying the 
CCOC and inner bypass ducts. Transport Canada AD CF-2022-22 also 
specifies an installation prohibition for flange bolts with part 
numbers MS9698-08 and MS9698-09 on the affected 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 ADDRESSES.

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 this State of Design 
Authority, it has notified the FAA of the unsafe condition described in 
the MCAI described above. The FAA is issuing this NPRM after 
determining that the unsafe condition described previously is likely to 
exist or develop on other products of these same type designs.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in Transport Canada AD CF-2022-22, described previously, except for any 
differences identified as exceptions in the regulatory text of this 
proposed AD and except as discussed under ``Differences Between This 
Proposed AD and the MCAI.''

Explanation of Required Compliance Information

    In the FAA's ongoing efforts to improve the efficiency of the AD 
process, the FAA developed a process to use some civil aviation 
authority (CAA) ADs as the primary source of information for compliance 
with requirements for corresponding FAA ADs. The FAA has since 
coordinated with other manufacturers and CAAs to use this process. As a 
result, the FAA proposes to incorporate by reference Transport Canada 
AD CF-2022-22 in the FAA final rule. This proposed AD would, therefore, 
require compliance with Transport Canada AD CF-2022-22 in its entirety 
through that incorporation, except for any differences identified as 
exceptions in the regulatory text of this proposed AD. Using common 
terms that are the same as the heading of a particular section in the 
Transport Canada AD does not mean that operators need comply only with

[[Page 4113]]

that section. For example, where the AD requirement refers to 
``Compliance,'' compliance with this AD requirement is not limited to 
the section titled ``Corrective Actions'' in Transport Canada AD CF-
2022-22. Service information required by the Transport Canada AD for 
compliance will be available at regulations.gov by searching for and 
locating Docket No. FAA-2023-0022 after the FAA final rule is 
published.

Differences Between This Proposed AD and the MCAI

    Where the service information referenced in Transport Canada AD CF-
2022-22 requires reporting certain information to the manufacturer, 
this proposed AD would not require reporting the information to the 
manufacturer.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 668 engines installed on airplanes of U.S. Registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Remove and replace all CCOC flange      1.5 work-hours x $85 per          $7,742          $7,870      $5,257,160
 bolts.                                  hour = $128.
Modify the CCOC and inner bypass ducts  1.5 work-hours x $85 per               0             128          85,504
                                         hour = $128.
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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

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

Pratt & Whitney Canada Corporation: Docket No. FAA-2023-0022; 
Project Identifier MCAI-2022-00564-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by March 10, 2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to:
    (1) Pratt & Whitney Canada (P&WC) PW308A model turbofan engines 
with build specification (BS) BS935 and BS1249, serial numbers PCE-
CE0180 and prior; and
    (2) P&WC PW308C model turbofan engines with BS1047 and BS1238, 
serial numbers PCE-CF0967 and prior.

(d) Subject

    Joint Aircraft Service Component (JASC) Code 7240, Turbine 
Engine Combustion Section.

(e) Unsafe Condition

    This AD was prompted by a manufacturer's design review which 
identified that the combustion chamber outer case (CCOC) to rear 
compressor case (RCC) flange bolts low cycle fatigue life was 
inadequate, and that those flange bolts may develop cracks resulting 
in flange bolt fracture. The FAA is issuing this AD to prevent 
cracking and fracture of the flange bolts. The unsafe condition, if 
not addressed, may result in flange bolt fracture, flange separation 
or case rupture, damage to the engine and damage to the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    Except as specified in paragraphs (h) and (i) of this AD: 
Perform all required actions within the compliance times specified 
in, and in accordance with, Transport Canada AD CF-2022-22.

(h) Exceptions to Transport Canada AD CF-2022-22

    Where Transport Canada AD CF-2022-22 requires compliance from 
its effective date, this AD requires using the effective date of 
this AD.

(i) No Reporting Requirement

    Although the service information referenced in Transport Canada 
AD CF-2022-22 specifies to submit certain information to the 
manufacturer, this AD does not include that requirement.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in Sec.  
39.19. In accordance with Sec.  39.19, send your request to your 
principal inspector or local Flight Standards District Office, as 
appropriate. If sending information directly to the manager of the 
certification office, send it to the attention of the person 
identified in paragraph (k) of this AD or email to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager

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of the local flight standards district office/certificate holding 
district office.

(k) Additional Information

    For more information about this AD, contact Barbara Caufield, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7146; email: 
[email protected].

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Transport Canada AD CF-2022-22, dated April 22, 2022.
    (ii) [Reserved]
    (3) For Transport Canada AD CF-2022-22, contact Transport 
Canada, Transport Canada National Aircraft Certification, 159 
Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; phone: (888) 663-
3639; email: [email protected]; website: tc.canada.ca/en/aviation.
    (4) 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 (817) 222-5110.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on January 17, 2023.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2023-01148 Filed 1-23-23; 8:45 am]
BILLING CODE 4910-13-P


