[Federal Register Volume 62, Number 152 (Thursday, August 7, 1997)]
[Rules and Regulations]
[Pages 42391-42397]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-20784]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-ANE-25-AD; Amendment 39-10094, AD 97-11-51 R1]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney PW2000 Series Turbofan 
Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to Pratt & Whitney PW2000 series turbofan engines. This 
action revises telegraphic AD T97-11-51 that currently supersedes AD 
97-09-01 by correcting errors in the Serial Number (S/N) tables, and 
removing the McDonnell Douglas C-17 aircraft from the applicability 
section, as a different model engine is installed on McDonnell Douglas 
C-17 aircraft. In addition, that telegraphic AD clarifies that 
inspections must be performed prior to rework, and clarifies that new 
parts do not need to be reworked prior to installation, but must be 
reworked at the next shop visit. Finally, that telegraphic AD makes 
minor editorial changes for clarity without changing meaning or intent. 
This action relaxes the compliance intervals for rework and provides 
relieving requirements. This amendment is prompted by industry input 
and resulting changes by the manufacturer to the inspection program 
that would provide relief to operators while maintaining an equivalent 
level of safety. The actions specified by this AD are intended to 
prevent fracture of the first stage high pressure turbine (HPT) disk, 
resulting in a possible uncontained engine failure and damage to the 
aircraft.

DATES: August 7, 1997.

[[Page 42392]]

    The incorporation by reference of certain publications listed in 
the regulations was approved by the Director of the Federal Register as 
of May 10, 1997.
    Comments for inclusion in the Rules Docket must be received on or 
before October 6, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 97-ANE-25-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain 
the docket number in the subject line.
    The service information referenced in this AD may be obtained from 
Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone (860) 
565-6600, fax (860) 565-4503. This information may be examined at the 
FAA, New England Region, Office of the Assistant Chief Counsel, 12 New 
England Executive Park, Burlington, MA; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., Suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: John Fisher, Aerospace Engineer, 
Engine Certificate Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (617) 
238-7149, fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: On May 12, 1997, the Federal Aviation 
Administration (FAA) issued telegraphic airworthiness directive (AD) 
T97-11-51, applicable to Pratt & Whitney (PW) PW2000 series turbofan 
engines, which supersedes AD 97-09-01 by correcting errors in the 
Serial Number (S/N) tables, and removing the McDonnell Douglas C-17 
aircraft from the applicability section, as a different model engine is 
installed on McDonnell Douglas C-17 aircraft. In addition, that AD 
clarifies that inspections must be informed prior to rework, and 
clarifies that new parts do not need to be reworked prior to 
installation, but must be reworked at the next shop visit. Finally, 
that AD makes minor editorial changes for clarity without changing 
meaning or intent. That action was prompted by comments from the 
manufacturer received in response to AD 97-09-01 that require the FAA 
to issue immediate changes and corrections to the compliance section 
prior to initiating the inspection and rework program described in the 
AD 97-09-01. Airworthiness directive 97-09-01 was prompted by reports 
of two uncontained disk failures resulting from a fir tree lug 
fracturing, that subsequently released two blades and a fir tree lug, 
that penetrated the engine high pressure turbine (HPT) case. That 
condition, if not corrected, could result in fracture of the first 
stage HPT disk, resulting in a possible uncontained engine failure and 
damage to the aircraft.
    Since the issuance of that telegraphic AD, the FAA has received 
changes from the manufacturer to the inspection program that would 
provide relief to operators while maintaining an equivalent level of 
safety.
    The FAA has reviewed and approved the technical contents of PW 
Service Bulletin (SB) No. PW2000 72-588, Revision 1, dated March 31, 
1997, and Original, dated February 17, 1997, that describe procedures 
for inspections for cracks in the forward face of the first stage HPT 
disk at the base of the fir tree lug at the outer diameter (OD) snap 
fillet radius where the side plates mate with the disk utilizing an 
eddy current inspection technique, and PW Alert Service Bulletin (ASB) 
No. PW2000 A72-592, dated March 18, 1997, that describes procedures for 
rework to the forward and aft faces of the first stage HPT disk OD snap 
fillet radii at the base of the fir tree lug.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of this same type design, this AD 
revises telegraphic AD T97-11-51 to relax the compliance intervals for 
rework and provide relieving requirements by adding an optional double 
independent eddy current inspection. The actions are required to be 
accomplished in accordance with the service documents described 
previously.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.
Comments Invited
    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications should identify the Rules Docket Number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-ANE-25-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will not have substantial direct 
effects 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. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, may 
be obtained from the Rules Docket at the location provided under the 
caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

[[Page 42393]]

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

97-11-51 R1  Pratt & Whitney: Amendment 39-10094. Docket No. 97-ANE-
25-AD. Revises AD T97-11-51.

    Applicability: Pratt & Whitney (PW) PW2000 series turbofan 
engines, with first stage high press turbine (HPT) disk assembly, 
Part Numbers (P/N) 1A5921, 1B2671, and 1B3621, installed. These 
engines are installed on but not limited to Boeing 757 series and 
Ilyushin IL-96 series aircraft.

    Note 1: This airworthiness directive (AD) applies to each engine 
identified in the preceding applicability provision, regardless of 
whether it has been modified, altered, or repaired in the area 
subject to the requirements of this AD. For engines that have been 
modified, altered, or repaired so that the performance of the 
requirements of this AD is affected, the owner/operator must request 
approval for an alternative method of compliance in accordance with 
paragraph (1) of this AD. The request should include an assessment 
of the effect of the modification, alteration, or repair on the 
unsafe condition addressed by this AD; and, if the unsafe condition 
has not been eliminated, the request should include specific 
proposed actions to address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fracture of the first stage HPT disk, resulting in a 
possible uncontained engine failure and damage to the aircraft, 
accomplish the following:
    (a) Prior to further flight, for first stage HPT disks that are 
accessible in the shop, on the effective date of this AD, as defined 
in paragraph (k)(2) of this AD, and that have not been eddy current 
inspected in accordance with the Accomplishment Instructions of PW 
Service Bulletin (SB) No. PW2000 72-588, Revision 1, dated March 31, 
1997, or Original, dated February 17, 1997, perform eddy current 
inspection (ECI) of the first stage HPT disks for cracks in the 
forward face of the disk at the base of the fir tree lug at the 
outer diameter (OD) snap fillet radius where the side plants mate 
with the disk, in accordance with the Accomplishment Instructions of 
PW SB No. PW2000 72-588, Revision 1, dated March 31, 1997, or 
Original, dated February 17, 1997.
    (b) For first stage HPT disks that are identified by serial 
number (S/N) in Table 1 of this AD, and have not been eddy current 
inspected in accordance with the Accomplishment Instructions of PW 
SB No. PW2000 72-588, Revision 1, dated March 31, 1997, or Original, 
dated February 17, 1997, accomplish the following:

                                                     Table 1                                                    
----------------------------------------------------------------------------------------------------------------
                                                                                                                
----------------------------------------------------------------------------------------------------------------
L82270.........         M68538          N11397          N54412          P36638          P91935          R28848  
L82271.........         M68539          N11398          N54413          P36639          R28552          R28901  
L82272.........         M68540          N11399          N54414          P36805          R28553          R28903  
L82356.........         M68541          N11400          N54415          P36806          R28554          R28904  
L82649.........         M68696          N11401          N54416          P37113          R28555          R28905  
L82650.........         M68697          N11402          N54417          P37114          R28612          R28906  
L83308.........         M68698          N11403          N54418          P37115          R28613          R28907  
L83309.........         M68699          N11404          N54419          P37116          R28614          R28908  
L83310.........         M68700          N11405          N55114          P37117          R28615          R28909  
L83311.........         M68701          N11406          N55115          P37118          R28617          R28913  
L83312.........         M68702          N11407          N55116          P37324          R28618          R28914  
M15709.........         M68703          N12830          N55117          P37325          R28680          R28915  
M15710.........         M68915          N12831          P00624          P37326          R28681          R28933  
M15718.........         M68916          N12832          P00625          P37327          R28682          R28934  
M42710.........         M68917          N12833          P00626          P37328          R28683          R28935  
M42711.........         M68918          N12834          P00627          P37348          R28684          R28936  
M42768.........         M68919          N12835          P00628          P37349          R28685          R28937  
M42769.........         M68997          N12836          P00788          P37351          R28686          R28951  
M42770.........         M68998          N12838          P00812          P37352          R28687          R28952  
M42771.........         M69000          N12839          P00813          P37353          R28711          R28953  
M43103.........         M69001          N12840          P00814          P37354          R28712          R28954  
M43104.........         M85382          N12841          P00815          P90203          R28713          R28955  
M43105.........         M85383          N12842          P00816          P90204          R28714          R28956  
M43396.........         M85384          N12843          P00817          P90205          R28715          S16633  
M43397.........         M85385          N12844          P00818          P90206          R28716          S16634  
M43398.........         M85386          N12845          P00986          P90207          R28718          S16636  
M43399.........         M85387          N12846          P00987          P90208          R28719          S16637  
M43400.........         N09764          N12847          P01018          P90209          R28720          S16638  
M43401.........         N09765          N12848          P01457          P90210          R28752          S16639  
M43409.........         N09766          N54390          P36249          P90211          R28753          S16641  
M43410.........         N09767          N54391          P36250          P90212          R28755          S16642  
M43411.........         N09768          N54392          P36251          P90385          R28756          S16643  
M68250.........         N09769          N54393          P36252          P90386          R28757          S16645  
M68251.........         N09770          N54395          P36253          P90387          R28758          S16646  
M68252.........         N09771          N54396          P36254          P90388          R28761          S16647  
M68253.........         N09772          N54397          P36255          P90389          R28800          S16648  
M68254.........         N09773          N54398          P36256          P90390          R28801          S16649  
M68255.........         N09774          N54399          P36258          P91685          R28802          S16650  
M68256.........         N09775          N54400          P36259          P91686          R28803          S16651  
M68344.........         N09776          N54401          P36306          P91687          R28804          S16658  
M68345.........         N09777          N54402          P36307          P91688          R28805          S16659  
M68346.........         N09778          N54403          P36308          P91854          R28806          S16660  
M68347.........         N11389          N54404          P36309          P91855          R28807          S16662  
M68348.........         N11390          N54405          P36310          P91856          R28808          S16666  
M68349.........         N11391          N54406          P36311          P91857          R28809          S16678  
M68350.........         N11392          N54407          P36312          P91867          R28810          S16687  

[[Page 42394]]

                                                                                                                
M68536.........         N11393          N54408          P36378          P91931          R28811                  
M68537.........         N11394          N54409          P36634          P91932          R28812                  
                        N11395          N54410          P36636          P91933          R28813                  
                        N11396          N54411          P36637          P91934          R28847                  
----------------------------------------------------------------------------------------------------------------

    (1) For disks that have accumulated 10,000 or more cycles since 
new (CSN) on the effective date of this AD, accomplish the 
following:
    (i) Perform an inspection for cracks and rework within 1,600 CIS 
after the effective date of this AD in accordance with PW ASB No. 
PW2000 A72-592, dated March 18, 1997, or

    Note 2: Throughout this AD, Pratt & Whitney ASB No. PW2000 A72-
592, dated March 18, 1997, describes returning the part to 
designated overhaul shops for modifications. The modifications 
described in that ASB are performed by the overhaul shops and 
include inspections prior to and after rework.

    (ii) Perform a double independent inspection for cracks, as 
defined in paragraph (k)(3) of this AD, within 1,600 cycles in 
service (CIS) after the effective date of this AD, in accordance 
with the Accomplishment Instructions of PW SB No. PW2000 72-588, 
Revision 1, dated March 31, 1997, or Original, dated February 17, 
1997.
    (iii) If the disk is double inspected in accordance with 
paragraph (b)(1)(ii) of this AD, then inspect the disk for cracks 
and rework at the next shop visit after the completion of the double 
inspection, but not to exceed 4,000 CIS since the double inspection, 
in accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (2) For disks that have accumulated less than 10,000 CSN on the 
effective date of this AD, accomplish the following:
    (i) Perform an inspection for cracks and rework at the next shop 
visit after the effective date of this AD, or 11,600 CSN, whichever 
occurs first, in accordance with PW ASB No. PW2000 A72-592, dated 
March 18, 1997, or
    (ii) Perform a double independent inspection for cracks, as 
defined in paragraph (k)(3) of this AD, at the next shop visit after 
the effective date of this AD, not to exceed 11,600 CSN, in 
accordance with the Accomplishment Instructions of PW SB No. PW2000 
72-588, Revision 1, dated March 31, 1997, or Original, dated 
February 17, 1997.
    (iii) If the disk is double inspected in accordance with 
paragraph (b)(2)(ii) of this AD, then inspect the disk for cracks 
and rework at the next shop visit after the completion of the double 
inspection, but not to exceed 4,000 CIS since the double inspection, 
in accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (c) For first stage HPT disks that are identified by S/N in 
Table 2 of this AD, and that have not been eddy current inspected in 
accordance with the Accomplishment Instructions of PW SB No. PW2000 
72-588, Revision 1, dated March 31, 1997, or Original, dated 
February 17, 1997, accomplish the following:

                                                     Table 2                                                    
----------------------------------------------------------------------------------------------------------------
                                                                                                                
----------------------------------------------------------------------------------------------------------------
D301AA0011...........             S16682                 S16713                 S16746                 S16780   
D301AA0032...........             S16683                 S16715                 S16747                 S16783   
S16652...............             S16684                 S16716                 S16748                 S16787   
S16654...............             S16685                 S16717                 S16749                 S16795   
S16655...............             S16688                 S16718                 S16750                          
S16656...............             S16689                 S16719                 S16751                          
S16657...............             S16690                 S16720                 S16752                          
S16661...............             S16691                 S16721                 S16753                          
S16663...............             S16692                 S16723                 S16756                          
S16664...............             S16693                 S16724                 S16757                          
S16665...............             S16694                 S16725                 S16758                          
S16667...............             S16695                 S16727                 S16760                          
S16668...............             S16697                 S16728                 S16761                          
S16669...............             S16698                 S16730                 S16762                          
S16670...............             S16699                 S16731                 S16763                          
S16671...............             S16700                 S16732                 S16765                          
S16672...............             S16701                 S16733                 S16766                          
S16673...............             S16702                 S16735                 S16768                          
S16674...............             S16703                 S16738                 S16769                          
S16675...............             S16705                 S16739                 S16772                          
S16676...............             S16707                 S16741                 S16773                          
S16677...............             S16708                 S16742                 S16774                          
S16679...............             S16709                 S16743                 S16775                          
S16680...............             S16710                 S16744                 S16776                          
S16681...............             S16712                 S16745                 S16777                          
----------------------------------------------------------------------------------------------------------------

    (1) For disks that have accumulated 7,000 or more CSN on the 
effective date of this AD, accomplish the following:
    (i) Perform an inspection for cracks and rework within 800 CIS 
after the effective date of this AD in accordance with PS ASB No. 
PW2000 A72-592, dated March 18, 1997, or
    (ii) Perform a double independent inspection for cracks, as 
defined in paragraph (k)(3) of this AD, within 800 CIS after the 
effective date of this AD, in accordance with the Accomplishment 
Instructions of PW SB No. PW2000 72-588, Revision 1, dated March 31, 
1997, or Original, dated February 17, 1997.
    (iii) If the disk is double inspected in accordance with 
paragraph (c)(1)(ii) of this AD, then inspect the disk for cracks 
and rework at the next shop visit after the completion of the double 
inspection, but not to exceed 4,000 CIS since the double inspection, 
in accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (2) For disks that have accumulated less then 7,000 CSN on the 
effective date of this AD, accomplish the following:
    (i) Perform an inspection for cracks and rework at the next shop 
visit after the effective date of this AD, or 7,800 CSN, whichever 
occurs first, in accordance with PW ASB No. PW2000 A72-592, dated 
March 18, 1997, or
    (ii) Perform a double independent inspection for cracks, as 
defined in paragraph (k)(3) of this AD, at the next shop visit after 
the effective date of this AD, not to exceed 7,800 CSN, in 
accordance with the Accomplishment Instructions of PW SB No. PW2000 
72-588, Revision 1, dated March 31, 1997, or Original, dated 
February 17, 1997.

[[Page 42395]]

    (iii) If the disk is double inspected in accordance with 
paragraph (c)(2)(ii) of this AD, then inspect the disk for cracks 
and rework at the next shop visit after the completion of the double 
inspection, but not to exceed 4,000 CIS since the double inspection, 
in accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (d) For first stage HPT disks that are identified by S/N in 
Table 3 of this AD, and that have not been eddy current inspected in 
accordance with the Accomplishment Instructions of PW SB No. PW2000 
72-588, Revision 1, dated March 31, 1997, or Original, dated 
February 17, 1997, accomplish the following:

                                                     Table 3                                                    
----------------------------------------------------------------------------------------------------------------
                                                                                                                
----------------------------------------------------------------------------------------------------------------
D301AA0002.......       D301AA0094         D301AA0371         DKLBA78442         DKLBA78551         DKLBA78661  
D301AA0003.......       D301AA0095         D301AA0372         DKLBA78443         DKLBA78552         DKLBAH8318  
D301AA0004.......       D301AA0096         D301AA0375         DKLBA78444         DKLBA78553         DKLBAH8319  
D301AA0005.......       D301AA0098         D301AA0376         DKLBA78446         DKLBA78554         DKLBAH8320  
D301AA0006.......       D301AA0101         D301AA0377         DKLBA78448         DKLBA78557         DKLBAH8321  
D301AA0008.......       D301AA0102         D301AA0379         DKLBA78449         DKLBA78558         DKLBAH8322  
D301AA0009.......       D301AA0103         D301AA0380         DKLBA78453         DKLBA78559         DKLBAH8323  
D301AA0010.......       D301AA0104         D301AA0381         DKLBA78454         DKLBA78560         DKLBAH8324  
D301AA0013.......       D301AA0105         D301AA0382         DKLBA78455         DKLBA78561         DKLBAH8325  
D301AA0015.......       D301AA0106         D301AA0383         DKLBA78456         DKLBA78562         DKLBAH8327  
D301AA0018.......       D301AA0107         D301AA0384         DKLBA78457         DKLBA78564         DKLBAH8328  
D301AA0019.......       D301AA0108         D301AA0386         DKLBA78458         DKLBA78568         DKLBAH8329  
D301AA0020.......       D301AA0110         D301AA0387         DKLBA78459         DKLBA78569         DKLBAH8330  
D301AA0021.......       D301AA0111         D301AA0388         DKLBA78465         DKLBA78575         DKLBAH8331  
D301AA0022.......       D301AA0114         D301AA0390         DKLBA78467         DKLBA78577         DKLBAH8332  
D301AA0023.......       D301AA0118         D301AA0391         DKLBA78468         DKLBA78578         DKLBAH8333  
D301AA0024.......       D301AA0121         D301AA0392         DKLBA78469         DKLBA78579         DKLBAH8336  
D301AA0025.......       D301AA0123         E301AA0393         DKLBA78472         DKLBA78580         DKLBAH8337  
D301AA0027.......       D301AA0124         E301AA0394         DKLBA78475         DKLBA78581         DKLBAH8339  
D301AA0028.......       D301AA0125         D301AA0395         DKLBA78482         DKLBA78582         DKLBAH8340  
D301AA0029.......       D301AA0127         D301AA0396         DKLBA78483         DKLBA78584         DKLBAH8343  
D301AA0031.......       D301AA0129         D301AA0399         DKLBA78484         DKLBA78585         DKLBAH8344  
D301AA0033.......       D301AA0130         D301AA0401         DKLBA78485         DKLBA78587         DKLBAH8346  
D301AA0034.......       D301AA0131         D301AA0402         DKLBA78486         DKLBA78589         DKLBAH8347  
D301AA0035.......       D301AA0132         D301AA0403         DKLBA78487         DKLBA78590         DKLBAH8348  
D301AA0038.......       D301AA0133         D301AA0404         DKLBA78488         DKLBA78593         DKLBAH8349  
D301AA0039.......       D301AA0135         D301AA0406         DKLBA78489         DKLBA78594         DKLBAH8350  
D301AA0040.......       D301AA0137         D301AA0407         DKLBA78490         DKLBA78596         DKLBAH8351  
D301AA0041.......       D301AA0138         D301AA0408         DKLBA78491         DKLBA78598         DKLBAH8352  
D301AA0042.......       D301AA0140         D301AA0412         DKLBA78492         DKLBA78600         DKLBAH8353  
D301AA0044.......       D301AA0141         D301AA0414         DKLBA78493         DKLBA78601         DKLBAH8354  
D301AA0045.......       D301AA0144         D301AA0415         DKLBA78496         DKLBA78603         DKLBAH8355  
D301AA0046.......       D301AA0145         D301AA0416         DKLBA78497         DKLBA78604         DKLBAH8356  
D301AA0047.......       D301AA0146         D301AA0418         DKLBA78498         DKLBA78605         DKLBAH8357  
D301AA0048.......       D301AA0147         D301AA0419         DKLBA78500         DKLBA78606         DKLBAH8360  
D301AA0049.......       D301AA0148         D301AA0420         DKLBA78502         DKLBA78607         DKLBAH8361  
D301AA0050.......       D301AA0149         D301AA0421         DKLBA78503         DKLBA78609         DKLBAH8362  
D301AA0051.......       D301AA0150         D301AA0422         DKLBA78504         DKLBA78610         DKLBAH8364  
D301AA0052.......       D301AA0151         D301AA0423         DKLBA78505         DKLBA78611         DKLBAH8365  
D301AA0053.......       D301AA0152         D301AA0424         DKLBA78506         DKLBA78613         DKLBAM0972  
D301AA0054.......       D301AA0154         D301AA0425         DKLBA78507         DKLBA78614         DKLBAM0973  
D301AA0055.......       D301AA0156         D301AA0426         DKLBA78508         DKLBA78615             S16778  
D301AA0056.......       D301AA0157         D301AA0427         DKLBA78509         DKLBA78616             S16782  
D301AA0057.......       D301AA0159         D301AA0428         DKLBA78510         DKLBA78617             S16784  
D301AA0059.......       D301AA0161         D301AA0431         DKLBA78512         DKLBA78618             S16786  
D301AA0061.......       D301AA0163         D301AA0432         DKLBA78514         DKLBA78620             S16789  
D301AA0062.......       D301AA0164         D301AA0434         DKLBA78515         DKLBA78622             S16790  
D301AA0064.......       D301AA0165         D301AA0435         DKLBA78517         DKLBA78625             S16792  
D301AA0065.......       D301AA0166         D301AA0437         DKLBA78518         DKLBA78627             S16793  
D301AA0066.......       D301AA0167         D301AA0438         DKLBA78519         DKLBA78628             S16798  
D301AA0067.......       D301AA0171         D301AA0439         DKLBA78520         DKLBA78632             S16800  
D301AA0068.......       D301AA0174         D301AA0440         DKLBA78521         DKLBA78633             S16802  
D301AA0069.......       D301AA0175         D301AA0443         DKLBA78522         DKLBA78635             S16803  
D301AA0070.......       D301AA0177         D301AA0444         DKLBA78524         DKLBA78636             S16804  
D301AA0071.......       D301AA0179         D301AA0445         DKLBA78525         DKLBA78638             S16805  
D301AA0072.......       D301AA0180         D301AA0446         DKLBA78526         DKLBA78639             S16806  
D301AA0074.......       D301AA0182         D301AA0447         DKLBA78527         DKLBA78640             S16807  
D301AA0075.......       D301AA0187         D301AA0449         DKLBA78528         DKLBA78642             S16808  
D301AA0077.......       D301AA0189         D301AA0450         DKLBA78529         DKLBA78644             S16810  
D301AA0080.......       D301AA0198         DKLBA78421         DKLBA78530         DKLBA78645             S16811  
D301AA0081.......       D301AA0201         DKLBA78423         DKLBA78531         DKLBA78646             S16814  
D301AA0082.......       D301AA0205         DKLBA78427         DKLBA78533         DKLBA78648             S16815  
D301AA0083.......       D301AA0358         DKLBA78429         DKLBA78534         DKLBA78649             S16816  
D301AA0084.......       D301AA0359         DKLBA78431         DKLBA78536         DKLBA78650             S16818  
D301AA0085.......       D301AA0360         DKLBA78432         DKLBA78537         DKLBA78651             S16819  
D301AA0086.......       D301AA0361         DKLBA78433         DKLBA78538         DKLBA78652             S16821  
D301AA0087.......       D301AA0362         DKLBA78434         DKLBA78540         DKLBA78653             S16822  

[[Page 42396]]

                                                                                                                
D301AA0088.......       D301AA0363         DKLBA78435         DKLBA78541         DKLBA78654             S16824  
D301AA0089.......       D301AA0364         DKLBA78436         DKLBA78542         DKLBA78655             S16825  
D301AA0090.......       D301AA0367         DKLBA78437         DKLBA78543         DKLBA78656             S16827  
D301AA0091.......       D301AA0368         DKLBA78438         DKLBA78544         DKLBA78657             S16829  
D301AA0092.......       D301AA0369         DKLBA78439         DKLBA78545         DKLBA78658             S16831  
D301AA0093.......       D301AA0370         DKLBA78441         DKLBA78550         DKLBA78660             S16832  
----------------------------------------------------------------------------------------------------------------

    (1) For disks that have accumulated 7,000 or more CSN on the 
effective date of this AD accomplish the following:
    (i) Perform an inspection for cracks and rework within 1,100 CIS 
after the effective date of this AD in accordance with PW ASB No. 
PW2000 A72-592, dated March 18, 1997, or
    (ii) Perform a double independent inspection for cracks, as 
defined in paragraph (k)(3) of this AD, within 1,100 CIS after the 
effective date of this AD, in accordance with the Accomplishment 
Instructions of PW SB No. PW2000 72-588, Revision 1, dated March 31, 
1997, or Original, dated February 17, 1997.
    (iii) If the disk is double inspected in accordance with 
paragraph (d)(1)(ii) of this AD, then inspect the disk for cracks 
and rework at the next shop visit after the completion of the double 
inspection, but not to exceed 2,450 CIS since the double inspection, 
in accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (2) For disks that have accumulated less than 7,000 CSN on the 
effective date of this AD, accomplish the following:
    (i) Perform an inspection for cracks and rework at the next shop 
visit after the effective date of this AD, or 8,100 CSN, whichever 
occurs first, in accordance with PW ASB No. PW2000 A72-592, dated 
March 18, 1997, or
    (ii) Perform a double independent inspection for cracks, as 
defined in paragraph (k)(3) of this AD, at the next shop visit after 
the effective date of this AD, not to exceed 8,100 CSN, in 
accordance with the Accomplishment Instructions of PW SB No. PW2000 
72-588, Revision 1, dated March 31, 1997, or Original, dated 
February 17, 1997.
    (iii) If the disk is double inspected in accordance with 
paragraph (d)(2)(ii) of this AD, then inspect the disk for cracks 
and rework at the next shop visit after the completion of the double 
inspection, but not to exceed 2,450 CIS since the double inspection, 
in accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (e) For disks that have been inspected in accordance with PW SB 
No. PW2000, 72-588, Revision 1, dated March 31, 1997, or Original, 
dated February 17, 1997, but not reworked in accordance with PW ASB 
No. PW2000 A72-592, dated March 18, 1997, inspect for cracks and 
rework in accordance with PW ASB No. PW2000 A72-592, dated March 18, 
1997, at the next shop visit when the part is accessible, as defined 
in paragraph (k)(2) of this AD, or 4,000 CIS since last ECI in 
accordance with PW SB No. PW2000 72-588, Revision 1, dated March 31, 
1997, or Original, dated February 17, 1997, whichever occurs first.
    (f) Prior to further flight, remove and replace disks with 
cracks. Disks with cracks cannot be reworked.
    (g) If reworked, reidentify the disk in accordance with the 
Accomplishment Instructions of PW ASB No. PW2000 A72-592, dated 
March 18, 1997.
    (h) For all first stage HPT disks that have been reworked in 
accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997, 
inspect in accordance with PW Engine Manual, P/N 1A6231, Section 72-
52-02, Inspection Check 04, at each subsequent shop visit when the 
disk is accessible, as defined in paragraph (k)(2) of this AD, not 
to exceed 6,000 CIS since last inspection.
    (i) The following cyclic life limits apply to disks that are 
reworked in accordance with the Accomplishment Instructions of PW 
ASB No. PW2000 A72-592, dated March 18, 1997:
    (1) Disks that have accumulated less than 5,000 CSN upon rework 
may accumulate an additional 10,000 CIS following rework, and then 
must be retired from service.
    (2) Disks that have accumulated 5,000 CSN or more upon rework 
may remain in service to the full 15,000 CSN published life limit, 
and then must be retired from service.
    (3) Except as provided in paragraph (1) of this AD, no 
alternative life limits may be approved for disks reworked in 
accordance with PW ASB No. PW2000 A72-592, dated March 18, 1997.
    (j) Operators may install new, unused first stage HPT disks 
without inspection and rework in accordance with PW ASB No. PW2000 
A72-592, dated March 18, 1997, but must inspect and rework those 
disks at the next shop visit when the disk is accessible, as defined 
in paragraph (k)(2) of this AD, or 6,500 CSN, whichever occurs 
first, in accordance with PW ASB No. PW2000 A72-592, dated March 18, 
1997, as defined in paragraphs (b) through (d), and (f) through (i) 
of this AD.
    (k) For the purpose of this AD, the following definitions apply:
    (1) A shop visit is defined as an engine removal where engine 
maintenance, prior to reinstalling the engine, entails separation of 
pairs of mating major engine flanges or the removal of a disk, hub, 
or spool.
    (2) An accessible disk is defined as a disk that is in the shop, 
has been removed from the HPT module, separated from the rotor, and 
debladed.
    (3) A double independent inspection is defined as having two 
independent qualified inspectors perform a complete ECI of the disk 
in accordance with the inspection requirements described in the 
Accomplishment Instructions of PW SB No. PW2000 72-588, Revision 1, 
dated March 31, 1997, or Original, dated February 17, 1997. Each 
inspector shall perform an independent calibration of the ECI 
equipment prior to performing the ECI in accordance with that SB.
    (l) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Engine Certification Office. 
Operators shall submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, Engine Certification Office.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Engine Certification Office.

    (m) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the aircraft to a location where 
the inspection and rework requirements of this AD can be 
accomplished.
    (n) The actions required by this AD shall be accomplished in 
accordance with the following PW service documents:

----------------------------------------------------------------------------------------------------------------
             Document No.                      Pages                   Revision                    Date         
----------------------------------------------------------------------------------------------------------------
SB No. PW2000                                                                                                   
72-588...............................  1....................  1........................  March 31, 1997.        
                                       2....................  Original.................  February 17, 1997.     
                                       3-12.................  1........................  March 31, 1997.        
NDIP-899.............................  1-23.................  A........................  March 25, 1997.        
                                       38...................  Original.................  February 17, 1997.     
    Total pages: 36                                                                                             
SB No. PW2000                                                                                                   

[[Page 42397]]

                                                                                                                
72-588...............................  1-12.................  Original.................  February 17, 1997.     
                                       38...................  Original.................  February 17, 1997.     
NDIP-899.............................  1-23.................  Original.................  February 16, 1997.     
    Total pages: 36                                                                                             
ASB No. PW2000                                                                                                  
A72-592..............................  1-16.................  Original.................  March 18, 1997.        
    Total pages: 16                                                                                             
----------------------------------------------------------------------------------------------------------------

    This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Copies may be obtained from Pratt & Whitney, 400 Main St., East 
Hartford, CT 06108; telephone (860) 565-6600, fax (860) 565-4503. 
Copies may be inspected at the FAA, New England Region, Office of the 
Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.
    (o) This amendment becomes effective on August 7, 1997.

    Issued in Burlington, Massachusetts, on July 25, 1997.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 97-20784 Filed 8-6-97; 8:45 am]
BILLING CODE 4910-13-M