[Federal Register Volume 77, Number 173 (Thursday, September 6, 2012)]
[Rules and Regulations]
[Pages 54791-54793]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-21821]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0228; Directorate Identifier 2012-NE-09-AD;
Amendment 39-17179; AD 2012-18-03]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney Division Turbofan
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 Division PW4000-94'' and PW4000-100'' turbofan engines
having a 1st stage high-pressure turbine (HPT) seal support, part
number (P/N) 55K601 (contained within assembly P/N 55K602-01) or P/N
50K532 (contained within assembly P/N 50K530-01), installed. This AD
was prompted by 58 reports of cracked 1st stage HPT air seal rings,
including 15 in-flight engine shutdowns. This AD requires removal and
replacement of the 1st stage HPT seal support and inspection of the 1st
stage HPT air seal ring. We are issuing this AD to prevent failure of
the 1st stage HPT air seal ring, which could lead to an internal oil
fire, uncontained engine failure, and damage to the airplane.
DATES: This AD is effective October 11, 2012.
ADDRESSES: 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. 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; 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 regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (phone: 800-647-5527) is Document Management Facility,
U.S. 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: James Gray, Aerospace Engineer, Engine
& Propeller Directorate, FAA, 12 New England Executive Park,
Burlington, MA 01803; phone: 781-238-7742; fax: 781-238-7199; email:
[email protected].
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM published in the Federal Register on April 20, 2012 (77 FR
23637). That NPRM proposed to require removal and replacement of the
1st stage HPT seal support and inspection of the 1st stage HPT air seal
ring.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
and the FAA's response to each comment.
Support for the NPRM
Commenter The Boeing Company supports the contents of the proposed
AD (77 FR 23637, April 20, 2012) as written.
Request To Add Credit for Prior Compliance
FedEx Express (FedEx) requested that the AD include credit for
previous compliance.
We agree. We added ``Comply with this AD the next time the HPT
module is removed from the engine, unless already done'' to paragraph
(e) of the AD.
Request To Change Compliance to Next Piece-Part Exposure
FedEx requested that we clarify that the required removal and
inspections occur when the part is completely disassembled and at the
piece-part level.
We do not agree. Removal of the 1st stage HPT seal support and
inspection of the 1st stage HPT air seal ring are required when the HPT
module is removed from the engine, which is not necessarily when the
parts are at the piece-part level. Performing the actions the next time
the HPT module is removed is required to maintain an acceptable level
of safety for the fleet. We did not change the AD.
Request To Add the P/N of the Affected 1st Stage HPT Air Seal Ring
Lufthansa Technik AG requested that we add the P/N of the 1st stage
HPT air seal ring that requires inspection to paragraph (e)(2) of the
proposed AD (77 FR 23637, April 20, 2012). The commenter states that
there are two air seals in this area of the engine and clarification
would help avoid confusion over which one requires inspection.
We agree. We revised paragraph (e)(2) of the AD to include 1st
stage HPT air seal ring, P/N 50L664.
Request To Change Compliance Time
Martinair requested that paragraph (e) of the proposed AD (77 FR
23637, April 20, 2012) be changed from ``* * * the next time that the
engine is separated at the M-flange and the HPT module is removed from
the engine'' to ``* * * the next time the HPT module is removed from
the engine.'' The commenter states that the wording is confusing and
may be interpreted that one is allowed to separate the engine at the M-
flange, without intending to remove the HPT module from the engine, and
therefore the support would not require replacement.
We agree. Including reference to the M-flange is redundant and not
required, since the M-flange must be separated for the HPT module to be
removed from the engine. We changed paragraph (e) of the AD to ``comply
with this AD the next time that the HPT module is removed from the
engine.''
Request To Reference the Latest Service Information
Pratt & Whitney (P&W) requested that the AD reference the latest
versions of service bulletins (SBs) PW4ENG 72-721 and PW4G-100-72-166
because they were revised since the proposed AD (77 FR 23637, April 20,
2012) was published.
We disagree. The service information is only included as related
information and is not incorporated by reference. Therefore, it is not
necessary to specify a revision level and date of the service
information in the AD. The proposed AD did include the revision level
and date, but we modified the AD to remove those details.
[[Page 54792]]
Request To Revise the P/Ns of the 1st Stage HPT Seal Support
Martinair, United, and P&W requested that the P/Ns of the 1st stage
HPT seal support be changed because the 1st stage HPT seal support P/N
is not generally tracked by itself, although the assembly P/N is. One
commenter recommended mandating full incorporation of P&W SBs PW4ENG
72-721 and PW4G-100-72-166, while another commenter recommended
including the assembly P/Ns.
We partially agree. We agree that the assembly P/Ns should be
included for clarity because the 1st stage HPT seal support is not
generally tracked by itself. The assembly includes the support and the
mating brush seal. Even though they are sold as sets and generally
tracked together, it is important to note that the unsafe condition has
been identified on the HPT seal support and not the brush seal. We
disagree that the SBs should be incorporated by reference because there
are multiple acceptable methods of performing the actions required by
the AD. We changed paragraph (e)(1) of the AD to ``Remove the 1st stage
HPT seal support, P/N 55K601 (contained within assembly P/N 55K602-01)
or P/N 50K532 (contained within assembly P/N 50K530-01), from service
and replace it with a serviceable 1st stage HPT seal support.''
Request To Revise the Cost of Compliance
United requested that we revise the costs of compliance because the
latest parts cost is $48,695, not $45,723, as stated in the proposed AD
(77 FR 23637, April 20, 2012).
We agree. We included the latest parts costs in the Costs of
Compliance paragraph of the AD.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
the AD with the changes described previously. We also determined that,
other than the updated parts cost, these changes will not increase the
economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
We estimate that this AD will affect 446 P&W PW4000-94'' and
PW4000-100'' turbofan engines installed on airplanes of U.S. registry.
We also estimate that it will take about 3 work-hours to perform the
removal and replacement of the 1st stage HPT seal support, and the
removal, inspection, and replacement if necessary of the 1st stage HPT
air seal ring. The average labor rate is $85 per work-hour. Required
parts will cost about $48,695 per engine. Based on these figures, we
estimate the total cost of the AD to U.S. operators to be $21,831,700.
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
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 that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in, 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):
2012-18-03 Pratt & Whitney Division: Amendment 39-17179; Docket No.
FAA-2012-0228; Directorate Identifier 2012-NE-09-AD.
(a) Effective Date
This AD is effective October 11, 2012.
(b) Affected ADs
None.
(c) Applicability
This AD applies to the following Pratt & Whitney Division
turbofan engines:
(1) PW4000-94'' engine models PW4050, PW4052, PW4056, PW4152,
PW4156, PW4650, PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4156A,
PW4158, PW4160, PW4460, and PW4462, including models with any dash-
number suffix, with a 1st stage high-pressure turbine (HPT) seal
support, part number (P/N) 55K601 (contained within assembly P/N
55K602-01) or P/N 50K532 (contained within assembly P/N 50K530-01),
installed.
(2) PW4000-100'' engine models PW4164, PW4164C, PW4164C/B,
PW4168, and PW4168A with a 1st stage HPT seal support, P/N 55K601
(contained within assembly P/N 55K602-01) or P/N 50K532 (contained
within assembly P/N 50K530-01), installed.
(d) Unsafe Condition
This AD was prompted by 58 reports of cracked 1st stage HPT air
seal rings, including 15 in-flight engine shutdowns. We are issuing
this AD to prevent failure of the 1st stage HPT air seal ring, which
could lead to an internal oil fire, uncontained engine failure, and
damage to the airplane.
(e) Compliance
Comply with this AD the next time the HPT module is removed from
the engine, unless already done.
(1) Remove the 1st stage HPT seal support, P/N 55K601 (contained
within assembly P/N 55K602-01) or P/N 50K532 (contained within
assembly P/N 50K530-01), from service and replace it with a
serviceable 1st stage HPT seal support.
(2) Remove the 1st stage HPT air seal ring, P/N 50L664, from the
engine and fluorescent-penetrant-inspect, or eddy current-inspect,
it for cracks. If found cracked, remove the 1st stage HPT air seal
ring from service.
(f) Definition
For the purpose of this AD, a serviceable 1st stage HPT seal
support is one that has a P/N that is not listed in this AD.
[[Page 54793]]
(g) 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.
(h) Related Information
(1) For more information about this AD, contact James Gray,
Aerospace Engineer, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; phone: 781-238-7742;
fax: 781-238-7199; email: [email protected].
(2) Pratt & Whitney Service Bulletin (SB) No. PWENG 72-721 and
SB No. PW4G-100-72-166, pertain to the subject of this AD.
(3) For service information identified in this AD, contact Pratt
& Whitney, 400 Main St., East Hartford, CT 06108; phone: 860-565-
8770; fax: 860-565-4503.
(i) Material Incorporated by Reference
None.
Issued in Burlington, Massachusetts, on August 16, 2012.
Colleen M. D'Alessandro,
Assistant Manager, Engine & Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2012-21821 Filed 9-5-12; 8:45 am]
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