[Federal Register Volume 70, Number 237 (Monday, December 12, 2005)]
[Rules and Regulations]
[Pages 73358-73361]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-23828]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-66-AD; Amendment 39-14402; AD 2005-25-09]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney PW4000 Series Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is superseding an existing airworthiness directive 
(AD) for Pratt & Whitney (PW) PW4000 series turbofan engines. That AD 
currently requires revisions to the engine manufacturer's time limits 
section (TLS) to include enhanced inspection of selected critical life-
limited parts at each piece-part opportunity. This AD modifies the 
airworthiness limitations section of the manufacturer's manuals and an 
air carrier's approved continuous airworthiness maintenance program by 
adding eddy current inspections for front compressor hubs installed in 
PW 4000-94'' engine models. This AD also adds the PW4062A engine to the 
applicability. An FAA study of in-service events involving uncontained 
failures of critical rotating engine parts has indicated the need for 
mandatory inspections. The mandatory inspections are needed to identify 
those critical rotating parts with conditions, which if allowed to 
continue in service, could result in uncontained failures. We are 
issuing this AD to prevent critical life-limited rotating engine part 
failure, which could result in an uncontained engine failure and damage 
to the airplane.

DATES: This AD becomes effective June 12, 2006.

ADDRESSES: You may examine the AD docket at the FAA, New England 
Region, Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7146, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a new AD, applicable to (PW) PW4000 series turbofan engines. We 
published the proposed AD in the Federal Register on August 18, 2004 
(69 FR 51200). We proposed to modify the airworthiness limitations 
section of the manufacturer's manuals and an air carrier's approved 
continuous airworthiness maintenance program to add eddy current 
inspections for front compressor hubs installed in PW 4000-94'' engine 
models (Engine Manuals 50A443, 50A605, and 50A22). We also proposed to 
add the PW4062A engine to the applicability.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8:00 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Change Costs of Compliance

    Four commenters request we change the costs of compliance to 
include the investment they have to make in equipment, to perform these 
inspections. We do not agree. This AD does not require operators to 
invest in equipment or to hire more personnel to comply with the AD. 
The AD requires revisions to the engine manufacturer's TLS to include 
enhanced inspection of selected critical life-limited parts at each 
piece-part opportunity. Operators can choose to buy equipment to 
perform the inspections or send the parts to an approved service 
provider for inspection.

Request for Lead Time To Purchase Eddy Current Inspection Equipment

    Three commenters request lead time of an additional 6-to-8 months, 
as they want to purchase eddy current inspection equipment. We agree. 
We changed the effective date of the AD to be 180 days after the date 
of publication.

Request for Special Eddy Current Inspection Instructions

    Two commenters request we provide special eddy current inspection 
instructions in the AD, as equipment sensitivity to surface finish, and 
to worn or previously repaired parts may cause ``liftoff'' resulting in 
false indications. We do not agree. The AD does not contain specific 
inspection instructions. The AD requires revisions to the engine 
manufacturer's TLS to include enhanced inspection of selected critical 
life-limited parts at each piece-part opportunity. The engine 
manufacturer and the suppliers of the eddy current inspection equipment 
provide the special inspection procedures and requirements.

Request To Allow Use of Equivalent Inspection Equipment

    One commenter requests we allow use of equivalent inspection 
equipment to perform the eddy current inspections, as some operators 
have already invested in equivalent eddy current inspection equipment. 
Using the single-source equipment specified by the engine manufacturer 
will cause an undue cost burden. We do not agree. The AD does not 
specify only one source of equipment for the inspections. The engine 
manufacturer developed validated inspection procedures using specific 
equipment that provides acceptable inspection methods. However, 
operators can seek approval to use equivalent equipment, using the 
Alternative Methods of Compliance procedures referenced in paragraph 
(h) of this AD or, they can send the part to an approved service 
provider for inspection.

Conclusion

    We carefully reviewed the available data, including the comments 
received, and determined that air safety and the public interest 
require adopting the AD with the changes described previously. We 
determined that these changes will neither increase the economic burden 
on any operator nor increase the scope of the AD.

Costs of Compliance

    About 2,625 Pratt & Whitney PW4000 series turbofan engines of the 
affected design are in the worldwide fleet. We estimate 600 engines 
installed on airplanes of U.S. registry will be affected by this AD. We 
also estimate it will take about 10 work hours per engine to perform 
the inspections, and the average labor rate is $65 per work hour. Since 
this is an added inspection requirement, included as part of the normal 
maintenance cycle, no additional part

[[Page 73359]]

costs are involved. Based on these figures, the total additional cost 
per engine per shop visit is estimated to be $650. Based on the current 
PW4000 engine shop visit rate, the total additional cost for the PW4000 
fleet is estimated to be $123,000 per year.

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 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); 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 summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 98-ANE-66-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration 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 removing Amendment 39-12649, (67 FR 
7061, June 4, 2002) and by adding a new airworthiness directive, 
Amendment 39-14402, to read as follows:

2005-25-09 Pratt & Whitney: Amendment 39-14402. Docket No. 98-ANE-
66-AD.

Effective Date

    (a) This AD becomes effective June 12, 2006.

Affected ADs

    (b) This AD supersedes AD 2002-03-08.

Applicability

    (c) This AD applies to Pratt & Whitney (PW) Models PW4050, 
PW4052, PW4056, PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4152, 
PW4156, PW4156A, PW4158, PW4160, PW4460, PW4462, PW4650, PW4164, 
PW4168, PW4168A, PW4074, PW4074D, PW4077, PW4077D, PW4084, PW4084D, 
PW4090, PW4090-3, PW4090D, and PW4098 turbofan engines. These 
engines are installed on but not limited to, Airbus A300, A310, and 
A330 series, Boeing 747, 767, and 777 series, and McDonnell Douglas 
MD-11 series airplanes.

Unsafe Condition

    (d) This AD results from the need to add additional inspection 
requirements for PW4000-94'' engine models only, and to add the 
PW4062A engine to the applicability. We are issuing this AD to 
prevent critical life-limited rotating engine part failure, which 
could result in an uncontained engine failure and damage to the 
airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.
    (f) Within the next 60 days after the effective date of this AD, 
revise the Time Limits Section (TLS) of the Engine Manuals (EMs), 
part numbers 50A443, 50A605, 50A822, 51A342, 51A345, and 51A751, as 
applicable, for PW Models PW4050, PW4052, PW4056, PW4060, PW4060A, 
PW4060C, PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, 
PW4460, PW4462, PW4650, PW4164, PW4168, PW4168A, PW4074, PW4074D, 
PW4077, PW4077D, PW4084, PW4084D, PW4090, PW4090-3, PW4090D, and 
PW4098 turbofan engines, and for air carriers, revise the approved 
continuous airworthiness maintenance program, by adding the 
following:

``MANDATORY INSPECTIONS

    (1) Perform inspections of the following parts at each piece-
part opportunity in accordance with the instructions provided in the 
PW4000 series Engine Cleaning, Inspection and Repair (CIR) Manuals:
    For Engine Manuals 50A443, 50A605, and 50A822, add the following 
table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Hub, Front Compressor.............  ALL...................        72-31-07  Insp/Check-02.......          51A357
Hub, Turbine, Front Assy (Stage 1)  ALL...................        72-52-05  Insp/Check-02.......          51A357
Hub, Turbine, Intermediate Rear     ALL...................        72-52-06  Insp/Check-02.......          51A357
 (Stage 2).
----------------------------------------------------------------------------------------------------------------

    For Engine Manual 51A342, add the following table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Hub, LPC Assembly.................  ALL...................        72-31-07  Insp/Check-02.......          51A357
Hub, Turbine, Front Assembly        ALL...................        72-52-05  Insp/Check-02.......          51A357
 (Stage 1).
Seal--Air, HPT Stage 2............  ALL...................        72-52-22  Insp/Check-02.......          51A357
Hub, Turbine, Rear (Stage 2)......  ALL...................        72-52-06  Insp/Check-02.......          51A357
----------------------------------------------------------------------------------------------------------------


[[Page 73360]]

    For Engine Manuals 51A345 and 51A751, add the following table 
data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Hub, LPC Assembly.................  ALL...................        72-31-07  Insp/Check-02.......          51A750
Seal--Air, HPT Stage 1............  ALL...................        72-52-19  Insp/Check-02.......          51A750
Hub, Turbine, Front Assembly        ALL...................        72-52-05  Insp/Check-02.......          51A750
 (Stage 1).
Seal--Air, HPT Stage 2 Assemply...  ALL...................        72-52-22  Insp/Check-02.......          51A750
Hub, Turbine Rear Assembly (Stage   ALL...................        72-52-06  Insp/Check-02.......          51A750
 2).
----------------------------------------------------------------------------------------------------------------

    For Engine Manuals 50A443, 50A605, and 50A822, add the following 
table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
HPC Stage 5 Disk..................  ALL...................        72-35-06  Insp/Check-02.......          51A357
HPC Front Drum Rotor..............  ALL...................        72-35-07  Insp/Check-02.......          51A357
HPC Rear Drum Rotor...............  ALL...................        72-35-08  Insp/Check-02.......          51A357
HPC Rear Drum Rotor...............  ALL...................        72-35-10  Insp/Check-02.......          51A357
----------------------------------------------------------------------------------------------------------------

    For Engine Manual 51A342, add the following table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
HPC Stage 5 Disk..................  ALL...................        72-35-06  Insp/Check-02.......          51A357
HPC Front Drum Rotor..............  ALL...................        72-35-07  Insp/Check-02.......          51A357
HPC Rear Drum Rotor...............  ALL...................        72-35-10  Insp/Check-02.......          51A357
----------------------------------------------------------------------------------------------------------------

    For Engine Manuals 51A345 and 51A751, add the following table 
data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
HPC Stage 5 Disk..................  ALL...................        72-35-06  Insp/Check-02.......          51A750
HPC Front Drum Rotor..............  ALL...................        72-35-07  Insp/Check-02.......          51A750
HPC Rear Drum Rotor...............  ALL...................        72-35-10  Insp/Check-02.......          51A750
HPC Stage 15 Disk.................  ALL...................        72-35-92  Insp/Check-02.......          51A750
HPT Stage 1 Airseal...............  ALL...................        72-52-19  Insp/Check-02.......          51A750
HPT Front Hub.....................  ALL...................        72-52-05  Insp/Check-02.......          51A750
HPT Stage 2 Airseal...............  ALL...................        72-52-22  Insp/Check-02.......          51A750
HPT Rear Hub......................  ALL...................        72-52-06  Insp/Check-02.......          51A750
----------------------------------------------------------------------------------------------------------------

    For Engine Manuals 50A443, 50A605 and 50A822, add the following 
table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Stage 3 LPT Disk..................  ALL...................        72-53-13  Insp/Check-02.......          51A357
Stage 4 LPT Disk..................  ALL...................        72-53-14  Insp/Check-02.......          51A357
Stage 5 LPT Disk..................  ALL...................        72-53-15  Insp/Check-02.......          51A357
Stage 6 LPT Disk..................  ALL...................        72-53-16  Insp/Check-02.......          51A357
----------------------------------------------------------------------------------------------------------------

    For Engine Manual 51A342, add the following table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Stage 3 LPT Disk..................  ALL...................        72-53-13  Insp/Check-02.......          51A357
Stage 4 LPT Disk..................  ALL...................        72-53-14  Insp/Check-02.......          51A357
Stage 5 LPT Disk..................  ALL...................        72-53-15  Insp/Check-02.......          51A357

[[Page 73361]]

 
Stage 6 LPT Disk..................  ALL...................        72-53-16  Insp/Check-02.......          51A357
Stage 7 LPT Disk..................  ALL...................        72-53-61  Insp/Check-02.......          51A357
----------------------------------------------------------------------------------------------------------------

    For Engine Manual 51A345, add the following table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Stage 3 LPT Disk..................  ALL...................        72-53-13  Insp/Check-02,                51A750
                                                                             Config-1.
Stage 4 LPT Disk..................  ALL...................        72-53-14  Insp/Check-02.......          51A750
Stage 5 LPT Disk..................  ALL...................        72-53-60  Insp/Check-02.......          51A750
Stage 6 LPT Disk..................  ALL...................        72-53-16  Insp/Check-02,                51A750
                                                                             Config-1.
Stage 7 LPT Disk..................  ALL...................        72-53-72  Insp/Check-02.......          51A750
Stage 8 LPT Disk..................  ALL...................        72-53-62  Insp/Check-02,                51A750
                                                                             Config-1.
Stage 9 LPT Disk..................  ALL...................        72-53-63  Insp/Check-02.......          51A750
----------------------------------------------------------------------------------------------------------------

    For Engine Manual 51A751, add the following table data:

----------------------------------------------------------------------------------------------------------------
                                                              CIR manual         CIR manual
         Part nomenclature                Part number           section          inspection         CIR manual
----------------------------------------------------------------------------------------------------------------
Stage 3 LPT Disk..................  ALL...................        72-53-13  Insp/Check-02,                51A750
                                                                             Config-2. See Note
                                                                             (1).
Stage 4 LPT Disk..................  ALL...................        72-53-14  Insp/Check-02.......          51A750
Stage 5 LPT Disk..................  ALL...................        72-53-60  Insp/Check-02.......          51A750
Stage 6 LPT Disk..................  ALL...................        72-53-16  Insp/Check-02,                51A750
                                                                             Config-2. See Note
                                                                             (1).
Stage 7 LPT Disk..................  ALL...................        72-53-72  Insp/Check-02.......          51A750
Stage 8 LPT Disk..................  ALL...................        72-53-62  Insp/Check-02,                51A750
                                                                             Config-2. See Note
                                                                             (1).
Stage 9 LPT Disk..................  ALL...................        72-53-63  Insp/Check-02.......         51A750
----------------------------------------------------------------------------------------------------------------
 (1) FPI method only.

    (2) For the purposes of these mandatory inspections, piece-part 
opportunity means:
    (i) The part is considered completely disassembled when done in 
accordance with the disassembly instructions in the manufacturer's 
engine manual to either part number level listed in the table above, 
and
    (ii) The part has accumulated more than 100 cycles in service 
since the last piece-part opportunity inspection, provided that the 
part was not damaged or related to the cause for its removal from 
the engine.''

Alternative Methods of Compliance

    (g) You must perform these mandatory inspections using the TLS 
and the applicable Engine Manual unless you receive approval to use 
an alternative method of compliance under paragraph (h) of this AD. 
Section 43.16 of the Federal Aviation Regulations (14 CFR 43.16) may 
not be used to approve alternative methods of compliance or 
adjustments to the times in which these inspections must be 
performed.
    (h) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Maintaining Records of the Mandatory Inspections

    (i) You have met the requirements of this AD by using a TLS of 
the manufacturer's engine manual changed as specified in paragraph 
(f) of this AD, and, for air carriers operating under part 121 of 
the Federal Aviation Regulations (14 CFR part 121), by modifying 
your continuous airworthiness maintenance plan to reflect those 
changes. You must maintain records of the mandatory inspections that 
result from those changes to the TLS according to the regulations 
governing your operation. You do not need to record each piece-part 
inspection as compliance to this AD. For air carriers operating 
under part 121, you may use either the system established to comply 
with section 121.369 or use an alternative system that your 
principal maintenance inspector has accepted if that alternative 
system:
    (1) Includes a method for preserving and retrieving the records 
of the inspections resulting from this AD; and
    (2) Meets the requirements of section 121.369(c); and
    (3) Maintains the records either indefinitely or until the work 
is repeated.
    (j) These record keeping requirements apply only to the records 
used to document the mandatory inspections required as a result of 
revising the TLS as specified in paragraph (f) of this AD, and do 
not alter or amend the record keeping requirements for any other AD 
or regulatory requirement.

Related Information

    (k) None.

    Issued in Burlington, Massachusetts, on December 5, 2005.
Carlos Pestana,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-23828 Filed 12-9-05; 8:45 am]
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