[Docket No. FAA-2015-3732; Directorate Identifier 2015-NE-25-AD[ 

RIN 2120-AA64 

Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop Engines AGENCY: Federal Aviation Administration (FAA). DOT. ACTION: Notice of proposed rnlemaking (NPRM). 

SUMMARY: We propose to adopt a new airworthiness directive (AD) for certain Pratt 

& Whitney Canada Corp. (PWC) PT6A-60AG, -65AG, -67AF, and -67AG turboprop 

engines. This proposed AD was prompted by incidents of corrosion and perforation of the 

two-ply Cu-Be bellows in Woodward fuel control units (FCUs). This proposed AD 

would require removing the Woodward FCU and installing an FCU that is eligible for 

installation. We are proposing this AD to prevent failure of the Woodward FCU, which 

could lead to failure of the engine, in-flight shutdown, and loss of control of the airplane. 

DATES: We must receive comments on this proposed AD by [INSERT DATE 60 

DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. 

ADDRESSES: You may send comments by any of the following methods: 

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the 

instructions for submitting comments. 

• Mail: Docket Management Facility, U.S. Department of Transportation, 1200 

New Jersey Avenue SE., West Building Ground Floor, Room W12-140, Washington, DC 

20590-0001. 

• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., 

Monday through Friday, except Federal holidays. 
information at the FAA, Engine & Propeller Directorate, 12 New England Executive 

Park, Burlington, MA. For information on the availability of this material at the FAA, 

call781-238-7125. 

Examining the AD Docket 

You may examine the AD docket on the Internet at http://wvvw.regulations.gov by 

searching for and locating Docket No. F AA-2015-3732; or in person at the Docket 

Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal 

holidays. The AD docket contains this proposed AD, the mandatory continuing 

airworthiness information (MCAI), the regulatory evaluation, any comments received, 

and other information. The address for the Docket Office (phone: 800-647-5527) is in the 

ADDRESSES section. Comments will be available in the AD docket shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: Besian Luga, Aerospace Engineer, 

Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; phone: 781-238-7750; fax: 781-238-7199; email: 

besian.luga@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written relevant data, views, or arguments about this 

proposed AD. Send your comments to an address listed under the ADDRESSES section. 

Include "Docket No. FAA-2015-3732; Directorate Identifier 2015-NE-25-AD" at the 

beginning of your comments. We specifically invite comments on the overall regulatory, 

economic, environmental, and energy aspects of this NPRM. We will consider all 

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also post a report summarizing each substantive verbal contact with FAA personnel 

concerning this NPRM. 

Discussion 

The Transport Canada Civil Aviation, which is the aviation authority for Canada, 

has issued Canada AD CF-2015-23, dated July 23, 2015 (referred to hereinafter as "the 

MCAI"), to correct an unsafe condition for the specified products. The MCAI states: 

There have been in-service incidents involving corrosion and 

perforation of the two-ply Cu-Be bellows in Woodward Fuel 

Control Units (FCU) fitred to PT6A-60, -65 and -67 series engines. 

In certain instances, associated bellows leakage has resulted in loss 

of engine power, in-flight shutdowns (IFSD) and even accidents. 

Engines installed on the aeroplanes that are used for crop dusting, 

due to the operational environment, are more susceptible to 

corrosion damage to the subject bellows. 

Loss of engine power or shut down in flight by itself usually is not 

considered a catastrophic event. However, on an aeroplane with 

single engine installation, an engine power loss or IFSD at a 

critical phase of flight could adversely affect the safe operation of 

the aeroplane. 

This AD affects the PT6A-60AG, PT6A-65AG, PT6A-67AF, and PT6A-67AG 

engine models because they have the affected Woodward FCUs installed. 

You may obtain further information by examining the MCAI in the AD docket on 

the Internet at http://www.regulations.gov by searching for and locating Docket No. 

FAA-2015-3732. 

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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 of this NPRM. 

FAA's Determination and Requirements of This Proposed AD 

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, they have notified us of the unsafe condition described in the MCAI and service 

information referenced above. We are proposing this AD because we evaluated all information provided by Transport Canada Civil Aviation and determined the unsafe 

condition exists and is likely to exist or develop on other products of the same type 

design. This NPRM would require replacing the Woodward FCU. 

Costs of Compliance 

We estimate that this proposed AD affects 341 engines installed on airplanes of 

U.S. registry. We also estimate that it would take about 1.5 hours per engine to comply 

with this proposed AD. The average labor rate is $85 per hour. Required parts cost about 

$1,000 per engine. Based on these figures, we estimate the cost of this proposed AD on 

U.S. operators to be $384,478. 

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. 

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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 

We detennined 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) Is not a "significant ntle" under the DOT Regulatory Policies and Procedures 

( 44 FR II 034, February 26, 1979), 

(3) Will not affect intrastate aviation in Alaska to the extent that it justifies 

making a regulatory distinction, and 

( 4) Will 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 CFRpart 39 as follows: 

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2. The FAA amends§ 39.13 by adding the following new airworthiness directive 

(AD): 

Pratt & Whitney Canada Corp. (Type Certificate previously held by Pratt & 

Whitney Canada, Inc., Pratt & Whitney Aircraft of Canada, Ltd., and United 

Aircraft of Canada, Ltd.): Docket No. FAA-2015-3732; Directorate Identifier 2015-

NE-25-AD. 

(a) Comments Due Date 

We must receive comments by [INSERT DATE 60 DAYS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to Pratt & Whitney 

and BS1048 with pre-SB No. PT6A-72-13402, 

PT6A-65AG, BS708, BS903, BS1101, and BS1!02 with pre-SB PT6A-72-13408, I _, ·.· 

:: ).:· -! 

: ·' ·; configuration; PT6A-67 AF; and PT6A-67 AG turboprop engines with 

Woodward fuel control units (FCUs) installed. 

(d) Reason 

This AD was prompted by incidents of corrosion and perforation of the two-ply 

Cu-Be bellows in Woodward FCUs. We are issuing this AD to prevent failure of the 

Woodward FCU, which could lead to failure of the engine, in-flight shutdown, and loss 

of control of the airplane. 

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Woodward FCU. Use paragraphs 3.A. and 3.C. ofPWC Service Bulletin (SB) No. PT6A72-14389, Revision 3, dated January 27, 2011 to replace the FCU. 

(2) For PWC PT6A-60AG BS919 and BS1048 engines with pre-SB No. PT6A72-13402 configuration, within 36 months after the effective date of this AD, replace the 

Woodward FCU. Use paragraph 3.C.(l) and 3.C.(3) ofPWC SB No. PT6A-72-13473, 

Revision 1, dated May 26,2015 to replace the FCU. 

(3) For PWC PT6A-65AG BS708, BS903, BSllOl, and BS1102 engines with 

pre-SB PT6A-72-13408 configuration, within 36 months after the effective date of this 

AD, replace the Woodward FCU. Use paragraphs 3.A.(l) and 3.A.(3) ofPWC SB No. 

PT6A-72-13473, Revision 1, dated May 26,2015 to replace the FCU. 

(f) Credit for Previous Actions 

You may take credit for the actions required by paragraph (e) of this AD if you 

performed the actions before the effective date of this AD in accordance with PWC SB 

No. PT6A-72-14389, Revision 2, dated April23, 2009; or SB No. PT6A-72-13473, dated 

March 12, 2015; or SB No. PT6A-72-13408, Revision 1, dated March 12, 2015; or earlier 

versions. 

(g) Alternative Methods of Compliance (AMOCs) 

The Manager, Engine Certification Office, FAA, may approve AMOCs for this 

AD. Use the procedures found in 14 CFR 39.19 to make your request. You may email 

your request to: ANE-AD-AMOC@faa.gov. 

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7199; email: besian.luga@faa.gov. 

(2) Refer to MCAI Transport Canada AD CF-2015-23, dated July 23, 2015, for 

more information. You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating it in Docket No. FAAw2015-

3732. 

(3) PWC SB No. PT6A-72-14389, Revision 3, dated January 27,2011 and SB 

No. 13473, Revision 1, dated May 26, 2015, can be obtained from PWC, using the 

contact information in paragraph (h)(4) of this proposed AD. 

( 4) For service information identified in this proposed AD, contact Pratt & 

Whitney Corp., 1000 Marie-Victorin, Longueuil, Quebec, Canada, J4G !AI; phone: 800-

268-8000; fax: 450-647-2888; Web site: www.pwc.ca. 

( 5) You may view this service information at the FAA, Engine & Propeller 

Directorate, 12 New England Executive Park, Burlington, MA. For information on the 

availability ofthis material at the FAA, call 781-238-7125. 

Issued in Burlington, Massachusetts, on November 4, 2015. 

Colleen M. D' Alessandro, 

Directorate Manager, Engine & Propeller Directorate, 

Aircraft Certification Service. 

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