Airworthiness Directives; Pratt & Whitney Canada Turboprop Engines

[Federal Register Volume 77, Number 89 (Tuesday, May 8, 2012)]
[Rules and Regulations]
[Pages 26943-26945]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-11057]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0417; Directorate Identifier 2012-NE-11-AD; 
Amendment 39-17045; AD 2012-09-10]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Canada Turboprop 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Pratt & Whitney Canada PT6A-38, -41, -42, -42A, -61, -64, -66, -66B, -
110, -112, -114, -114A, -121, -135, and -135A series turboprop engines. 
This AD requires removal from service of certain part manufacturer 
approval (PMA) replacement Timken Alcor Aerospace Technologies, Inc. 
(TAATI) first stage sun gears and planet gears installed in the 
reduction gearbox. This AD was prompted by failures of certain first 
stage sun gears manufactured by TAATI. We are issuing this AD to 
prevent failure of the sun gear and planet gears which will result in 
an engine in-flight shut down, possible uncontained engine failure, 
aircraft damage, and serious injuries.

DATES: This AD becomes effective May 23, 2012.
    We must receive comments on this AD by June 22, 2012.

ADDRESSES: You may send comments by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
    <bullet> Mail: U.S. Department of Transportation, 1200 New Jersey 
Avenue SE., West Building Ground Floor, Room W12-140, Washington, DC 
20590-0001.
    <bullet> Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    <bullet> Fax: 202-493-2251.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; 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 AD, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Operations office (phone: 800-647-5527) is the same as the 
Mail address provided in the ADDRESSES section. Comments will be 
available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Paul Craig, Aerospace Engineer, Los 
Angeles Aircraft Certification Office, FAA, 3960 Paramount Blvd., Suite 
100, Lakewood, CA 90712; phone: 562-627-5252; fax: 562-627-5210; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We received two reports of sun gears, part number (P/N) E3028456, 
and installed in reduction gearboxes, failing during operation. We also 
received one report of a sun gear, P/N E3037304, showing premature wear 
and broken gear teeth during inspection. All three gear failures 
occurred between 60 and 127 hours of operation time-since-new. These 
conditions, if not corrected, could result in failure of the sun gear 
and planet gears in the propeller reduction gearbox assembly, which 
will result in an engine in-flight shut down, possible uncontained 
engine failure, aircraft damage, and serious injuries. We determined 
that the affected PMA replacement TAATI first stage sun gears and 
planet gears listed in this AD, would have been installed after 
December 22, 2008. The affected parts are listed as follows:
    First stage sun gears P/N E3028456, all serial numbers (S/Ns), and 
the associated planet gears.

[[Page 26944]]

    First stage sun gears P/N E3037304, all S/Ns, and the associated 
planet gears.
    Planet gear sets P/N E3101455-02, all S/Ns, and the associated sun 
gears.
    Planet gear sets P/N E3101525-02, all S/Ns, and the associated sun 
gears.

FAA's Determination

    We are issuing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

AD Requirements

    This AD requires removal from service within 40 operating hours 
after the effective date of the AD, of the PMA replacement TAATI first 
stage sun gears and planet gears, as listed in the Discussion section 
above, and installed in the reduction gearbox assemblies of Pratt & 
Whitney Canada PT6A-38, -41, -42, -42A, -61, -64, -66, -66B, -110, -
112, -114, -114A, -121, -135, and -135A series turboprop engines.

FAA's Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD. The FAA has found that the risk to the flying public justifies 
waiving notice and comment prior to adoption of this rule because of 
the short compliance time required in this AD to start the inspections. 
Therefore, we determined that notice and opportunity for public comment 
before issuing this AD are impracticable and that good cause exists for 
making this amendment effective in fewer than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not precede it by notice and opportunity for public 
comment. We invite you to send any written relevant data, views, or 
arguments about this AD. Send your comments to an address listed under 
the ADDRESSES section. Include ``Docket No. FAA-2012-0417; Directorate 
Identifier 2012-NE-11-AD'' at the beginning of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this AD. We will consider all 
comments received by the closing date and may amend this AD because of 
those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this AD. Using the search function of the 
Web site, anyone can find and read the comments in any of our dockets, 
including, if provided, the name of the individual who sent the comment 
(or signed the comment on behalf of an association, business, labor 
union, etc.). You may review the DOT's complete Privacy Act Statement 
in the Federal Register published on April 11, 2000 (65 FR 19477-78).

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 Procedures (44 FR 11034, February 26, 1979); and
    3. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket.

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 AD:

2012-09-10 Pratt & Whitney Canada: Amendment 39-17045; Docket No. 
FAA-2012-0417; Directorate Identifier 2012-NE-11-AD.

(a) Effective Date

    This airworthiness directive (AD) becomes effective May 23, 
2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pratt & Whitney Canada PT6A-38, -41, -42, -
42A, -61, -64, -66, -66B, -110, -112, -114, -114A, -121, -135, and -
135A series turboprop engines:
    (1) That have had maintenance done to the power section module 
involving first stage sun gear or planet gear replacement since 
December 22, 2008; and
    (2) That have any of the following Timken Alcor Aerospace 
Technologies, Inc. (TAATI) part manufacturer approval (PMA) 
replacement first stage sun gears or planet gear sets installed:
    (i) First stage sun gears P/N E3028456, all serial numbers (S/
Ns).
    (ii) First stage sun gears P/N E3037304, all S/Ns.
    (iii) Planet gear sets P/N E3101455-02, all S/Ns.
    (iv) Planet gear sets P/N E3101525-02, all S/Ns.

(d) Unsafe Condition

    This AD was prompted by failures of certain first stage sun 
gears, manufactured by TAATI. We are issuing this AD to prevent 
failure of the sun gear and planet gears in the propeller reduction 
gearbox assembly, which will result in an engine in-flight shut 
down, possible uncontained engine failure, aircraft damage, and 
serious injuries.

(e) Compliance

    (1) Comply with this AD within the compliance times specified, 
unless already done.
    (2) Within 40 operating hours after the effective date of this 
AD, remove from service the following PMA replacement TAATI first 
stage sun gear and the planet gears from the propeller reduction 
gearbox assembly:
    (i) First stage sun gears P/N E3028456, all S/Ns, and the 
associated planet gears.
    (ii) First stage sun gears P/N E3037304, all S/Ns, and the 
associated planet gears.

[[Page 26945]]

    (iii) Planet gear sets P/N E3101455-02, all S/Ns, and the 
associated sun gears.
    (iv) Planet gear sets P/N E3101525-02, all S/Ns, and the 
associated sun gears.

(f) Installation Prohibition

    After the effective date of this AD, do not install on any 
airplane, any engine or power section module with a TAATI PMA 
replacement first stage sun gear or a planet gear set, as listed in 
paragraph (c) of this AD.

(g) Alternative Methods of Compliance (AMOCs)

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

(h) Special Flight Permits

    Special flight permits are not authorized.

(i) Related Information

    For more information about this AD, contact Paul Craig, 
Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, 
3960 Paramount Blvd., Suite 100, Lakewood, CA 90712; phone: 562-627-
5252; fax: 562-627-5210; email: [email protected].

(j) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on May 3, 2012.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-11057 Filed 5-7-12; 8:45 am]
BILLING CODE 4910-13-P

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