
[Federal Register Volume 79, Number 126 (Tuesday, July 1, 2014)]
[Rules and Regulations]
[Pages 37171-37173]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-14955]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-1009; Directorate Identifier 2013-NE-35-AD; 
Amendment 39-17855; AD 2014-11-05]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Canada Corp. Turboprop 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Pratt & Whitney Canada Corp. (P&WC) turboprop engines. This AD requires 
installing a reinforcement liner to the power turbine (PT) containment 
ring and, for certain PT containment rings, adding scallops. This AD 
was prompted by in-service events involving the perforation of engine 
cases as a result of the liberation of PT blades and the fracture/
displacement of the PT containment ring. We are issuing this AD to 
prevent uncontained engine failure and damage to the airplane.

DATES: This AD becomes effective August 5, 2014.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of August 5, 
2014.

ADDRESSES: For service information identified in this AD, contact Pratt 
& Whitney Canada Corp., 1000 Marie-Victorin, Longueuil, Quebec, Canada, 
J4G 1A1; phone: 800-268-8000; fax: 450-647-2888; Internet: www.pwc.ca. 
You may view this service 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, call 781-
238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2013-
1009; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this 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 
Document Management Facility, U.S.

[[Page 37172]]

Department of Transportation, Docket Operations, M-30, West Building 
Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 
20590.

FOR FURTHER INFORMATION CONTACT: Robert Green, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: (781) 238-
7754; fax: (781) 238-7199; email: robert.green@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to the specified products. The 
NPRM was published in the Federal Register on January 7, 2014 (79 FR 
763). The NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    There have been in-service events involving the perforation of 
PT6A small series engine cases as a result of the loss of integrity 
of Power Turbine (PT) Containment Rings under failure loads. 
Perforation of engine cases has been seen to result from the 
liberation of PT blades and from fracture/displacement of the PT 
Containment Ring itself.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received.

Request To Add Engine Models to the List of Applicable Engines

    Friend Aircare requested that we add the engine models listed in 
P&WC Service Bulletin (SB) No. 12076, Revision 3, dated January 17, 
1992, to the applicability of this AD because that SB requires the same 
modification to the PT containment ring assembly.
    We agree. We revised paragraph (c) of this AD by adding certain 
serial numbers of the following P&WC engine models: PT6A-11, PT6A-11AG, 
PT6A-15AG, PT6A-110, PT6A-112, and PT6A-121. We revised paragraph (e) 
of this AD to specify use of either P&WC SB No. 12076, Revision 3, 
dated January 17, 1992; or P&WC SB No. PT6A-72-A1427, Revision 3, dated 
January 27, 2012, as applicable. We revised paragraph (f) of this AD by 
adding credit for corrective actions taken in accordance with P&WC SB 
No. 12076, Revision 2, dated April 24, 1991, or earlier versions.

Request To Exclude Engines Used on Single-Engine Aircraft

    Reabe Spraying Services, Inc. requested that we exclude from 
applicability engines used on single-engine aircraft, or aircraft where 
the engine has nothing alongside of it that would sustain damage from 
release of debris.
    We disagree. We consider the uncontained release of engine hardware 
to be an unsafe condition. We did not change this AD.

Request To Withdraw the NPRM

    Dynamic Aviation requested that the FAA withdraw the NPRM (79 FR 
763, January 7, 2014). Dynamic Aviation has not experienced any PT disk 
blade failure in 16 years and 800,000 flight hours.
    We disagree. There have been in-service events involving the 
perforation of PT6A series engine cases as a result of the loss of 
integrity of the PT containment rings under failure loads. Perforation 
of engine cases has been seen to result from the liberation of PT 
blades and from fracture/displacement of the PT containment ring 
itself. We consider the release of engine hardware to be an unsafe 
condition. This AD requires the incorporation of P&WC SB No. 12076, 
Revision 3, dated January 17, 1992, or P&WC SB No. PT6A-72-A1427, 
Revision 3, dated January 27, 2012, as applicable, to prevent 
uncontained events. We did not change this AD.

Requests To Extend the Period of Compliance

    Dynamic Aviation requested that we change the compliance time from 
within 24 months after the effective date of this AD, to within 36 to 
48 months after the effective date of this AD. Dynamic Aviation said 
the extended compliance period would better allow the complete 
modification of all engines.
    Ameriflight LLC requested that we reconsider the period of 
compliance to allow a longer, more realistic timeframe for compliance.
    We agree. The compliance period can be increased without an 
appreciable risk effect. We revised paragraph (e)(2) of this AD to 
read, ``Within 48 months after the effective date of this AD, modify 
the existing PT containment ring.''

Request To More Accurately Estimate the Time Required To Modify an 
Engine

    Several entities requested that the estimated time and costs of 
compliance for completing the requirements of this AD more accurately 
reflect the actual time required to modify an engine.
    We agree. In the NPRM (79 FR 763, January 7, 2014), we based our 
estimate of 3 hours to modify an engine on original equipment 
manufacturer service information. Further analysis indicates this 
estimate is inadequate. We increased the estimated hours required to 
modify an engine from 3 hours to 20 hours.

Conclusion

    We reviewed the available data, including the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously. We determined that these 
changes will not increase the economic burden on any operator or 
increase the scope of this AD.

Costs of Compliance

    We estimate that this AD affects 1,000 engines installed on 
airplanes of U.S. registry. We estimate that it will take about 20 
hours per engine to comply with this AD. The average labor rate is $85 
per hour. Required parts cost about $1,655 per engine. Based on these 
figures, we estimate the cost of this AD on U.S. operators to be 
$3,355,000.

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.
    We are 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

    We determined that this AD will not have federalism implications 
under Executive Order 13132. This AD will 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 AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the DOT Regulatory Policies 
and

[[Page 37173]]

Procedures (44 FR 11034, 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.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 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 (AD):

2014-11-05 Pratt & Whitney Canada Corp.: Amendment 39-17855; Docket 
No. FAA-2013-1009; Directorate Identifier 2013-NE-35-AD.

(a) Effective Date

    This AD becomes effective August 5, 2014.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pratt & Whitney Canada Corp. (P&WC) turboprop 
engines as follows: all model PT6A-20, PT6A-20A, PT6A-20B, PT6A-25, 
PT6A-28, PT6A-34B, PT6A-36, and PT6A-135 engines; model PT6A-11 
engines, serial number (S/N) PC-E10539 and earlier; PT6A-11AG, S/N 
PC-E10224 and earlier; PT6A-15AG engines, S/N earlier than PC-
E14089; model PT6A-21 engines, S/N PCE-25361 and earlier; model 
PT6A-25A engines, S/N PCE-48757 and earlier; model PT6A-25C engines, 
S/N PCE-26258 and earlier; model PT6A-27 engines, S/N PCE-42523 and 
earlier as well as all engines converted to PT6A-27; model PT6A-34 
engines, S/N PCE-57303 and earlier as well as all engines converted 
to PT6A-34; model PT6A-34AG engines, S/N PCE-57312 and earlier as 
well as all engines converted to PT6A-34AG; model PT6A-110 engines, 
S/N PC-E15052 and earlier; model PT6A-112 engines, S/N earlier than 
PC-E12563; model PT6A-114 engines, S/N PCE-17218 and earlier; and 
model PT6A-135A engines, S/N PCE-35089 and earlier.

(d) Reason

    This AD was prompted by in-service events involving the 
perforation of engine cases as a result of the liberation of power 
turbine (PT) blades and the fracture/displacement of the PT 
containment ring. We are issuing this AD to prevent uncontained 
engine failure and damage to the airplane.

(e) Actions and Compliance

    (1) Comply with this AD within the compliance times specified, 
unless already done.
    (2) Within 48 months after the effective date of this AD, modify 
the existing PT containment ring. Use paragraph 2, Accomplishment 
Instructions, of P&WC Service Bulletin (SB) No. 12076, Revision 3, 
dated January 17, 1992, or paragraph 3, Accomplishment Instructions, 
P&WC SB No. PT6A-72-A1427, Revision 3, dated January 27, 2012, as 
applicable, to make the modification.

(f) Credit for Previous Actions

    If you modified the PT containment ring before the effective 
date of this AD using P&WC SB No. 12076, Revision 2, dated April 24, 
1991, or earlier versions, or P&WC SB No. PT6A-72-A1427, Revision 2, 
dated April 3, 1990, or earlier versions, you have met the 
requirements of this AD.

(g) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
to this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(h) Related Information

    (1) For more information about this AD, contact Robert Green, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: (781) 238-7754; fax: (781) 238-7199; email: 
robert.green@faa.gov.
    (2) Refer to MCAI Transport Canada Civil Aviation AD CF-2013-
33R1, dated November 14, 2013, for more information. You may examine 
the MCAI in the AD docket on the Internet at http://www.regulations.gov/#!documentDetail;D=FAA-2013-1009-0003.

(i) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) 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) Pratt & Whitney Canada (P&WC) Corp. Service Bulletin (SB) 
No. PT6A-72-A1427, Revision 3, dated January 27, 2012.
    (ii) P&WC, Inc. SB No. 12076, Revision 3, dated January 17, 
1992.
    (3) For P&WC service information identified in this AD, contact 
Pratt & Whitney Canada Corp., 1000 Marie-Victorin, Longueuil, 
Quebec, Canada, J4G 1A1; phone: 800-268-8000; fax: 450-647-2888; 
Internet: www.pwc.ca.
    (4) You may view this service information at FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, 
MA. For information on the availability of this material at the FAA, 
call 781-238-7125.
    (5) You may view this service information at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to: 
http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Burlington, Massachusetts, on May 22, 2014.
Colleen M. D'Alessandro,
Assistant Directorate Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2014-14955 Filed 6-30-14; 8:45 am]
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