Airworthiness Directives; Pratt & Whitney Division Turbofan Engines, 16967-16968 [2012-6965]
Download as PDF
Federal Register / Vol. 77, No. 57 / Friday, March 23, 2012 / Proposed Rules
[FR Doc. 2012–6992 Filed 3–22–12; 8:45 am]
BILLING CODE 3410–02–C
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2012–0079; Directorate
Identifier 2012–NE–06–AD]
RIN 2120–AA64
Airworthiness Directives; Pratt &
Whitney Division Turbofan Engines
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
We propose to adopt a new
airworthiness directive (AD) for Pratt &
Whitney PW4052, PW4152, PW4056,
PW4156A, PW4060, PW4060A,
PW4060C, PW4062, PW4062A,
PW4158, PW4460, PW4462, PW4164,
PW4164C, PW4164C/B, PW4168, and
PW4168A turbofan engines with certain
high-pressure turbine (HPT) stage 1
front hubs installed. This proposed AD
was prompted by Pratt & Whitney’s
updated low-cycle-fatigue analysis that
indicated certain HPT stage 1 front hubs
could initiate a crack prior to the
published life limit. This proposed AD
would require removing the affected
HPT stage 1 front hubs from service
using a drawdown plan. We are
proposing this AD to prevent failure of
the HPT stage 1 front hub, which could
lead to an uncontained engine failure
and damage to the airplane.
DATES: We must receive comments on
this proposed AD by May 22, 2012.
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 proposed AD, contact Pratt &
Whitney, 400 Main St., East Hartford,
CT 06108; phone: 860–565–7700; fax:
860–565–1605. You may review copies
of the referenced service information at
TKELLEY on DSK3SPTVN1PROD with PROPOSALS
SUMMARY:
VerDate Mar<15>2010
19:39 Mar 22, 2012
Jkt 226001
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 https://
www.regulations.gov; 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 proposed AD, the
regulatory evaluation, any comments
received, and other information. The
street 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:
James Gray, Aerospace Engineer, Engine
Certification Office, FAA, 12 New
England Executive Park, Burlington,
MA; phone: 781–238–7742; fax: 781–
238–7199; email: james.e.gray@faa.gov.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written
relevant data, views, or arguments about
this proposal. Send your comments to
an address listed under the ADDRESSES
section. Include ‘‘Docket No. FAA–
2012–0079; Directorate Identifier 2012–
NE–06–AD’’ at the beginning of your
comments. We specifically invite
comments on the overall regulatory,
economic, environmental, and energy
aspects of this proposed AD. We will
consider all comments received by the
closing date and may amend this
proposed AD because of those
comments.
We will post all comments we
receive, without change, to https://
www.regulations.gov, including any
personal information you provide. We
will also post a report summarizing each
substantive verbal contact we receive
about this proposed AD.
Discussion
A PW2000 field event led Pratt &
Whitney to re-evaluate the low-cycle
fatigue analysis of the PW2000 engine
and similar engine models, including
the PW4000 engine. Pratt & Whitney’s
updated analysis indicated that the
original grain size requirement specified
on the HPT stage 1 front hub design
drawing was too large, and may not be
sufficient to meet the published life
limits. Although we have not received
any reports of cracks, parts with the
larger grain size may initiate a crack
prior to the published life limits. This
condition, if not corrected, could result
PO 00000
Frm 00017
Fmt 4702
Sfmt 4702
16967
in failure of the HPT stage 1 front hub,
which could lead to an uncontained
engine failure and damage to the
airplane.
Relevant Service Information
We reviewed Pratt & Whitney Service
Bulletin (SB) No. PW4ENG 72–795,
Revision 2, dated April 5, 2011, and SB
No. PW4G–100–72–220, Revision 4,
dated September 30, 2011. The SBs list
the serial numbers of HPT stage 1 front
hubs with part number (P/N) 51L901
that are NOT affected by this AD.
However, all serial numbers of HPT
stage 1 front hubs with P/N 51L201,
P/N 51L201–001, P/N 51L601, and
P/N 52L401 are affected.
FAA’s Determination
We are proposing 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.
Proposed AD Requirements
This proposed AD would require
removing the affected HPT stage 1 front
hubs from service using a drawdown
plan.
Costs of Compliance
We estimate that this proposed AD
would affect 954 engines installed on
airplanes of U.S. registry. About 605
engines use a 20,000 cycles-since new
(CSN) life limit for the HPT stage 1 front
hub. For these engines, we estimate the
lost part life to have a value of about
$25,400 per engine. About 349 engines
use a 15,000 CSN life limit. For these
engines, we estimate the lost life to have
a value of about $22,013 per engine.
Based on these figures, we estimate the
total cost of the proposed AD to U.S.
operators is $23,049,537.
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
E:\FR\FM\23MRP1.SGM
23MRP1
16968
Federal Register / Vol. 77, No. 57 / Friday, March 23, 2012 / Proposed Rules
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 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 rule’’ under
the DOT Regulatory Policies and
Procedures (44 FR 11034, February 26,
1979),
(3) Will not affect intrastate aviation
in Alaska, 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 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.
§ 39.13
[Amended]
2. The FAA amends § 39.13 by adding
the following new airworthiness
directive (AD):
Pratt & Whitney Division: Docket No. FAA–
2012–0079; Directorate Identifier 2012–
NE–06–AD.
TKELLEY on DSK3SPTVN1PROD with PROPOSALS
(a) Comments Due Date
We must receive comments by May 22,
2012.
(b) Affected ADs
None.
(c) Applicability
This AD applies to the following Pratt &
Whitney Division turbofan engines:
(1) PW4052, PW4152, and PW4056
turbofan engines, including models with any
dash number suffix, with the following high-
VerDate Mar<15>2010
17:08 Mar 22, 2012
Jkt 226001
pressure turbine (HPT) stage 1 front hub part
numbers (P/Ns) installed:
(i) P/N 51L201, or P/N 51L201–001, or
P/N 51L601, or P/N 52L401; or
(ii) P/N 51L901 with a serial number (S/N)
not listed in Table 9 of the Accomplishment
Instructions of Pratt & Whitney Service
Bulletin (SB) No. PW4ENG 72–795, Revision
2, dated April 5, 2011.
(2) PW4156A, PW4060, PW4060A,
PW4060C, PW4062, PW4062A, PW4158,
PW4460, and PW4462 turbofan engines,
including models with any dash number
suffix, with the following HPT stage 1 front
hub P/Ns installed:
(i) P/N 51L201, or P/N 51L201–001, or
P/N 52L401; or
(ii) P/N 51L901 with an S/N not listed in
Table 9 of the Accomplishment Instructions
of Pratt & Whitney SB No. PW4ENG 72–795,
Revision 2, dated April 5, 2011.
(3) PW4164, PW4164C, PW4164C/B,
PW4168, and PW4168A turbofan engines
with an HPT stage 1 front hub P/N 51L901
installed with a S/N not listed in Table 27A
of the Accomplishment Instructions of Pratt
& Whitney SB No. PW4G–100–72–220,
Revision 4, dated September 30, 2011.
(d) Unsafe Condition
This AD was prompted by Pratt &
Whitney’s updated low-cycle-fatigue analysis
that indicated certain HPT stage 1 front hubs
could initiate a crack prior to the published
life limit. This AD requires removing the
affected HPT stage 1 front hubs from service
using a drawdown plan. We are issuing this
AD to prevent failure of the HPT stage 1 front
hub, which could lead to an uncontained
engine failure and damage to the airplane.
(e) Compliance
Comply with this AD within the
compliance times specified, unless already
done.
(f) Removal of HPT Stage 1 Front Hubs From
Service
(1) For HPT stage 1 front hubs listed in
paragraph (c)(1)(i) and (c)(1)(ii) of this AD, do
the following:
(i) If the HPT stage 1 front hub has
accumulated 17,000 or fewer cycles-since
new (CSN) on the effective date of this AD,
remove the HPT stage 1 front hub from
service before accumulating 18,000 CSN.
(ii) If the HPT stage 1 front hub has
accumulated more than 17,000 CSN on the
effective date of this AD, remove the HPT
stage 1 front hub from service before
accumulating an additional 1,000 cycles-inservice (CIS), or at the next piece-part
exposure after the effective date of this AD,
whichever occurs first.
(2) For HPT stage 1 front hubs listed in
paragraphs (c)(2)(i), (c)(2)(ii), and (c)(3) of
this AD, do the following:
(i) If the HPT stage 1 front hub has
accumulated 12,700 or fewer CSN on the
effective date of this AD, remove the HPT
stage 1 front hub from service before
accumulating 13,700 CSN.
(ii) If the HPT stage 1 front hub has
accumulated more than 12,700 CSN on the
effective date of this AD, remove the HPT
stage 1 front hub from service before
accumulating an additional 1,000 CIS, or at
PO 00000
Frm 00018
Fmt 4702
Sfmt 4702
the next piece-part exposure after the
effective date of this AD, whichever occurs
first.
(g) Installation Prohibition
After the effective date of this AD, do not
install or reinstall into any engine any HPT
stage 1 front hubs listed in paragraph (c)(1)(i)
and (c)(1)(ii) of this AD that are at piece-part
exposure and exceed 18,000 CSN, or any
HPT stage 1 front hubs listed in (c)(2)(i),
(c)(2)(ii), and (c)(3) of this AD that are at
piece-part exposure and exceed 13,700 CSN.
(h) Definition
For the purpose of this AD, piece-part
exposure means that the part is completely
disassembled and removed from the engine.
(i) Alternative Methods of Compliance
(AMOCs)
The Manager, Engine Certification Office,
may approve AMOCs for this AD. Use the
procedures found in 14 CFR 39.19 to make
your request.
(j) Related Information
(1) For more information about this AD,
contact James Gray, Aerospace Engineer,
Engine Certification Office, FAA, 12 New
England Executive Park, Burlington, MA;
phone: 781–238–7742; fax: 781–238–7199;
email: james.e.gray@faa.gov.
(2) For service information identified in
this AD, contact Pratt & Whitney, 400 Main
St., East Hartford, CT 06108; phone: 860–
565–7700; fax: 860–565–1605.
(3) You may review copies of the
referenced 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.
Issued in Burlington, Massachusetts, on
March 14, 2012.
Peter A. White,
Manager, Engine & Propeller Directorate,
Aircraft Certification Service.
[FR Doc. 2012–6965 Filed 3–22–12; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2012–0324; Directorate
Identifier 2012–CE–008–AD]
RIN 2120–AA64
Airworthiness Directives; Burkhart
GROB Luft- und Raumfahrt GmbH
Powered Sailplanes
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
We propose to adopt a new
airworthiness directive (AD) for
SUMMARY:
E:\FR\FM\23MRP1.SGM
23MRP1
Agencies
[Federal Register Volume 77, Number 57 (Friday, March 23, 2012)]
[Proposed Rules]
[Pages 16967-16968]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-6965]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0079; Directorate Identifier 2012-NE-06-AD]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney Division Turbofan
Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: We propose to adopt a new airworthiness directive (AD) for
Pratt & Whitney PW4052, PW4152, PW4056, PW4156A, PW4060, PW4060A,
PW4060C, PW4062, PW4062A, PW4158, PW4460, PW4462, PW4164, PW4164C,
PW4164C/B, PW4168, and PW4168A turbofan engines with certain high-
pressure turbine (HPT) stage 1 front hubs installed. This proposed AD
was prompted by Pratt & Whitney's updated low-cycle-fatigue analysis
that indicated certain HPT stage 1 front hubs could initiate a crack
prior to the published life limit. This proposed AD would require
removing the affected HPT stage 1 front hubs from service using a
drawdown plan. We are proposing this AD to prevent failure of the HPT
stage 1 front hub, which could lead to an uncontained engine failure
and damage to the airplane.
DATES: We must receive comments on this proposed AD by May 22, 2012.
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 proposed AD, contact
Pratt & Whitney, 400 Main St., East Hartford, CT 06108; phone: 860-565-
7700; fax: 860-565-1605. You may review copies of the referenced
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 https://www.regulations.gov; 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 proposed AD, the regulatory
evaluation, any comments received, and other information. The street
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: James Gray, Aerospace Engineer, Engine
Certification Office, FAA, 12 New England Executive Park, Burlington,
MA; phone: 781-238-7742; fax: 781-238-7199; email:
james.e.gray@faa.gov.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2012-0079;
Directorate Identifier 2012-NE-06-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD because of those comments.
We will post all comments we receive, without change, to https://www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.
Discussion
A PW2000 field event led Pratt & Whitney to re-evaluate the low-
cycle fatigue analysis of the PW2000 engine and similar engine models,
including the PW4000 engine. Pratt & Whitney's updated analysis
indicated that the original grain size requirement specified on the HPT
stage 1 front hub design drawing was too large, and may not be
sufficient to meet the published life limits. Although we have not
received any reports of cracks, parts with the larger grain size may
initiate a crack prior to the published life limits. This condition, if
not corrected, could result in failure of the HPT stage 1 front hub,
which could lead to an uncontained engine failure and damage to the
airplane.
Relevant Service Information
We reviewed Pratt & Whitney Service Bulletin (SB) No. PW4ENG 72-
795, Revision 2, dated April 5, 2011, and SB No. PW4G-100-72-220,
Revision 4, dated September 30, 2011. The SBs list the serial numbers
of HPT stage 1 front hubs with part number (P/N) 51L901 that are NOT
affected by this AD. However, all serial numbers of HPT stage 1 front
hubs with P/N 51L201, P/N 51L201-001, P/N 51L601, and P/N 52L401 are
affected.
FAA's Determination
We are proposing 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.
Proposed AD Requirements
This proposed AD would require removing the affected HPT stage 1
front hubs from service using a drawdown plan.
Costs of Compliance
We estimate that this proposed AD would affect 954 engines
installed on airplanes of U.S. registry. About 605 engines use a 20,000
cycles-since new (CSN) life limit for the HPT stage 1 front hub. For
these engines, we estimate the lost part life to have a value of about
$25,400 per engine. About 349 engines use a 15,000 CSN life limit. For
these engines, we estimate the lost life to have a value of about
$22,013 per engine. Based on these figures, we estimate the total cost
of the proposed AD to U.S. operators is $23,049,537.
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
[[Page 16968]]
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 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 rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, 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 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 (AD):
Pratt & Whitney Division: Docket No. FAA-2012-0079; Directorate
Identifier 2012-NE-06-AD.
(a) Comments Due Date
We must receive comments by May 22, 2012.
(b) Affected ADs
None.
(c) Applicability
This AD applies to the following Pratt & Whitney Division
turbofan engines:
(1) PW4052, PW4152, and PW4056 turbofan engines, including
models with any dash number suffix, with the following high-pressure
turbine (HPT) stage 1 front hub part numbers (P/Ns) installed:
(i) P/N 51L201, or P/N 51L201-001, or P/N 51L601, or P/N 52L401;
or
(ii) P/N 51L901 with a serial number (S/N) not listed in Table 9
of the Accomplishment Instructions of Pratt & Whitney Service
Bulletin (SB) No. PW4ENG 72-795, Revision 2, dated April 5, 2011.
(2) PW4156A, PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4158,
PW4460, and PW4462 turbofan engines, including models with any dash
number suffix, with the following HPT stage 1 front hub P/Ns
installed:
(i) P/N 51L201, or P/N 51L201-001, or P/N 52L401; or
(ii) P/N 51L901 with an S/N not listed in Table 9 of the
Accomplishment Instructions of Pratt & Whitney SB No. PW4ENG 72-795,
Revision 2, dated April 5, 2011.
(3) PW4164, PW4164C, PW4164C/B, PW4168, and PW4168A turbofan
engines with an HPT stage 1 front hub P/N 51L901 installed with a S/
N not listed in Table 27A of the Accomplishment Instructions of
Pratt & Whitney SB No. PW4G-100-72-220, Revision 4, dated September
30, 2011.
(d) Unsafe Condition
This AD was prompted by Pratt & Whitney's updated low-cycle-
fatigue analysis that indicated certain HPT stage 1 front hubs could
initiate a crack prior to the published life limit. This AD requires
removing the affected HPT stage 1 front hubs from service using a
drawdown plan. We are issuing this AD to prevent failure of the HPT
stage 1 front hub, which could lead to an uncontained engine failure
and damage to the airplane.
(e) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(f) Removal of HPT Stage 1 Front Hubs From Service
(1) For HPT stage 1 front hubs listed in paragraph (c)(1)(i) and
(c)(1)(ii) of this AD, do the following:
(i) If the HPT stage 1 front hub has accumulated 17,000 or fewer
cycles-since new (CSN) on the effective date of this AD, remove the
HPT stage 1 front hub from service before accumulating 18,000 CSN.
(ii) If the HPT stage 1 front hub has accumulated more than
17,000 CSN on the effective date of this AD, remove the HPT stage 1
front hub from service before accumulating an additional 1,000
cycles-in-service (CIS), or at the next piece-part exposure after
the effective date of this AD, whichever occurs first.
(2) For HPT stage 1 front hubs listed in paragraphs (c)(2)(i),
(c)(2)(ii), and (c)(3) of this AD, do the following:
(i) If the HPT stage 1 front hub has accumulated 12,700 or fewer
CSN on the effective date of this AD, remove the HPT stage 1 front
hub from service before accumulating 13,700 CSN.
(ii) If the HPT stage 1 front hub has accumulated more than
12,700 CSN on the effective date of this AD, remove the HPT stage 1
front hub from service before accumulating an additional 1,000 CIS,
or at the next piece-part exposure after the effective date of this
AD, whichever occurs first.
(g) Installation Prohibition
After the effective date of this AD, do not install or reinstall
into any engine any HPT stage 1 front hubs listed in paragraph
(c)(1)(i) and (c)(1)(ii) of this AD that are at piece-part exposure
and exceed 18,000 CSN, or any HPT stage 1 front hubs listed in
(c)(2)(i), (c)(2)(ii), and (c)(3) of this AD that are at piece-part
exposure and exceed 13,700 CSN.
(h) Definition
For the purpose of this AD, piece-part exposure means that the
part is completely disassembled and removed from the engine.
(i) Alternative Methods of Compliance (AMOCs)
The Manager, Engine Certification Office, may approve AMOCs for
this AD. Use the procedures found in 14 CFR 39.19 to make your
request.
(j) Related Information
(1) For more information about this AD, contact James Gray,
Aerospace Engineer, Engine Certification Office, FAA, 12 New England
Executive Park, Burlington, MA; phone: 781-238-7742; fax: 781-238-
7199; email: james.e.gray@faa.gov.
(2) For service information identified in this AD, contact Pratt
& Whitney, 400 Main St., East Hartford, CT 06108; phone: 860-565-
7700; fax: 860-565-1605.
(3) You may review copies of the referenced 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.
Issued in Burlington, Massachusetts, on March 14, 2012.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 2012-6965 Filed 3-22-12; 8:45 am]
BILLING CODE 4910-13-P