AD 97-11-51 R1

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AD Number:
97-11-51 R1
Document Type:
AD Final Rules
Docket Number:
97-ANE-25-AD
Subject Heading:
Airworthiness Directives; Pratt & Whitney PW2000 Series Turbofan Engines
Subject:
First Stage High Pressure Turbine (HPT) Disk Assembly
Status:
Current
Citation:
Federal Register: August 07, 1997 (Volume 62, Number 152)
Citation Publish Date:
08/07/1997
Effective Date:
05/10/1997
Make:
Pratt & Whitney Division
Model:
PW2037 | PW2037M | PW2040 | PW2043 | PW2143 | PW2240 | PW2337 | PW2643
Product Type:
Engine
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39 [62 FR 42391 NO. 152 08/07/97]
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 97-11-51 R1
CITATION:   [Federal Register: August 07, 1997 (Volume 62, Number 152)]

PAGE NUMBER:   [Page 42391]

DOCKET NUMBER:   97-ANE-25-AD

AMENDMENT:   39-10094

AD NUMBER:   97-11-51 R1

SUBJECT HEADING:   Airworthiness Directives; Pratt & Whitney PW2000 Series Turbofan Engines

ACTION:   Final rule; request for comments.

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:   Effective August 7, 1997. 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-engineprop@faa.dot.gov". 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 Certification 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 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 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.
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. § 39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive:

REGULATORY TEXT:   97-11-51 R1 Pratt & Whitney: Amendment 39-10094. Docket No. 97-ANE-25-AD. Revises Telegraphic AD T97-11-51.
Applicability: Pratt & Whitney (PW) PW2000 series turbofan engines, with first stage high pressure 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 (l) 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 plates 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
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 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 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 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 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.
(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	D301AA0118	D301AA0414	DKLBA78514	DKLBA78646
D301AA0003	D301AA0121	D301AA0415	DKLBA78515	DKLBA78648
D301AA0004	D301AA0123	D301AA0416	DKLBA78517	DKLBA78649
D301AA0005	D301AA0124	D301AA0418	DKLBA78518	DKLBA78650
D301AA0006	D301AA0125	D301AA0419	DKLBA78519	DKLBA78651
D301AA0008	D301AA0127	D301AA0420	DKLBA78520	DKLBA78652
D301AA0009	D301AA0129	D301AA0421	DKLBA78521	DKLBA78653
D301AA0010	D301AA0130	D301AA0422	DKLBA78522	DKLBA78654
D301AA0013	D301AA0131	D301AA0423	DKLBA78524	DKLBA78655
D301AA0015	D301AA0132	D301AA0424	DKLBA78525	DKLBA78656
D301AA0018	D301AA0133	D301AA0425	DKLBA78526	DKLBA78657
D301AA0019	D301AA0135	D301AA0426	DKLBA78527	DKLBA78658
D301AA0020	D301AA0137	D301AA0427	DKLBA78528	DKLBA78660
D301AA0021	D301AA0138	D301AA0428	DKLBA78529	DKLBA78661
D301AA0022	D301AA0140	D301AA0431	DKLBA78530	DKLBAH8318
D301AA0023	D301AA0141	D301AA0432	DKLBA78531	DKLBAH8319
D301AA0024	D301AA0144	D301AA0434	DKLBA78533	DKLBAH8320
D301AA0025	D301AA0145	D301AA0435	DKLBA78534	DKLBAH8321
D301AA0027	D301AA0146	D301AA0437	DKLBA78536	DKLBAH8322
D301AA0028	D301AA0147	D301AA0438	DKLBA78537	DKLBAH8323
D301AA0029	D301AA0148	D301AA0439	DKLBA78538	DKLBAH8324
D301AA0031	D301AA0149	D301AA0440	DKLBA78540	DKLBAH8325
D301AA0033	D301AA0150	D301AA0443	DKLBA78541	DKLBAH8327
D301AA0034	D301AA0151	D301AA0444	DKLBA78542	DKLBAH8328
D301AA0035	D301AA0152	D301AA0445	DKLBA78543	DKLBAH8329
D301AA0038	D301AA0154	D301AA0446	DKLBA78544	DKLBAH8330
D301AA0039	D301AA0156	D301AA0447	DKLBA78545	DKLBAH8331
D301AA0040	D301AA0157	D301AA0449	DKLBA78550	DKLBAH8332
D301AA0041	D301AA0159	D301AA0450	DKLBA78551	DKLBAH8333
D301AA0042	D301AA0161	DKLBA78421	DKLBA78552	DKLBAH8336
D301AA0044	D301AA0163	DKLBA78423	DKLBA78553	DKLBAH8337
D301AA0045	D301AA0164	DKLBA78427	DKLBA78554	DKLBAH8339
D301AA0046	D301AA0165	DKLBA78429	DKLBA78557	DKLBAH8340
D301AA0047	D301AA0166	DKLBA78431	DKLBA78558	DKLBAH8343
D301AA0048	D301AA0167	DKLBA78432	DKLBA78559	DKLBAH8344
D301AA0049	D301AA0171	DKLBA78433	DKLBA78560	DKLBAH8346
D301AA0050	D301AA0174	DKLBA78434	DKLBA78561	DKLBAH8347
D301AA0051	D301AA0175	DKLBA78435	DKLBA78562	DKLBAH8348
D301AA0052	D301AA0177	DKLBA78436	DKLBA78564	DKLBAH8349
D301AA0053	D301AA0179	DKLBA78437	DKLBA78568	DKLBAH8350
D301AA0054	D301AA0180	DKLBA78438	DKLBA78569	DKLBAH8351
D301AA0055	D301AA0182	DKLBA78439	DKLBA78575	DKLBAH8352
D301AA0056	D301AA0187	DKLBA78441	DKLBA78577	DKLBAH8353
D301AA0057	D301AA0189	DKLBA78442	DKLBA78578	DKLBAH8354
D301AA0059	D301AA0198	DKLBA78443	DKLBA78579	DKLBAH8355
D301AA0061	D301AA0201	DKLBA78444	DKLBA78580	DKLBAH8356
D301AA0062	D301AA0205	DKLBA78446	DKLBA78581	DKLBAH8357
D301AA0064	D301AA0358	DKLBA78448	DKLBA78582	DKLBAH8360
D301AA0065	D301AA0359	DKLBA78449	DKLBA78584	DKLBAH8361
D301AA0066	D301AA0360	DKLBA78453	DKLBA78585	DKLBAH8362
D301AA0067	D301AA0361	DKLBA78454	DKLBA78587	DKLBAH8364
D301AA0068	D301AA0362	DKLBA78455	DKLBA78589	DKLBAH8365
D301AA0069	D301AA0363	DKLBA78456	DKLBA78590	DKLBAM0972
D301AA0070	D301AA0364	DKLBA78457	DKLBA78593	DKLBAM0973
D301AA0071	D301AA0367	DKLBA78458	DKLBA78594	S16778
D301AA0072	D301AA0368	DKLBA78459	DKLBA78596	S16782
D301AA0074	D301AA0369	DKLBA78465	DKLBA78598	S16784
D301AA0075	D301AA0370	DKLBA78467	DKLBA78600	S16786
D301AA0077	D301AA0371	DKLBA78468	DKLBA78601	S16789
D301AA0080	D301AA0372	DKLBA78469	DKLBA78603	S16790
D301AA0081	D301AA0375	DKLBA78472	DKLBA78604	S16792
D301AA0082	D301AA0376	DKLBA78475	DKLBA78605	S16793
D301AA0083	D301AA0377	DKLBA78482	DKLBA78606	S16798
D301AA0084	D301AA0379	DKLBA78483	DKLBA78607	S16800
D301AA0085	D301AA0380	DKLBA78484	DKLBA78609	S16802
D301AA0086	D301AA0381	DKLBA78485	DKLBA78610	S16803
D301AA0087	D301AA0382	DKLBA78486	DKLBA78611	S16804
D301AA0088	D301AA0383	DKLBA78487	DKLBA78613	S16805
D301AA0089	D301AA0384	DKLBA78488	DKLBA78614	S16806
D301AA0090	D301AA0386	DKLBA78489	DKLBA78615	S16807
D301AA0091	D301AA0387	DKLBA78490	DKLBA78616	S16808
D301AA0092	D301AA0388	DKLBA78491	DKLBA78617	S16810
D301AA0093	D301AA0390	DKLBA78492	DKLBA78618	S16811
D301AA0094	D301AA0391	DKLBA78493	DKLBA78620	S16814
D301AA0095	D301AA0392	DKLBA78496	DKLBA78622	S16815
D301AA0096	D301AA0393	DKLBA78497	DKLBA78625	S16816
D301AA0098	D301AA0394	DKLBA78498	DKLBA78627	S16818
D301AA0101	D301AA0395	DKLBA78500	DKLBA78628	S16819
D301AA0102	D301AA0396	DKLBA78502	DKLBA78632	S16821
D301AA0103	D301AA0399	DKLBA78503	DKLBA78633	S16822
D301AA0104	D301AA0401	DKLBA78504	DKLBA78635	S16824
D301AA0105	D301AA0402	DKLBA78505	DKLBA78636	S16825
D301AA0106	D301AA0403	DKLBA78506	DKLBA78638	S16827
D301AA0107	D301AA0404	DKLBA78507	DKLBA78639	S16829
D301AA0108	D301AA0406	DKLBA78508	DKLBA78640	S16831
D301AA0110	D301AA0407	DKLBA78509	DKLBA78642	S16832
D301AA0111	D301AA0408	DKLBA78510	DKLBA78644	
D301AA0114	D301AA0412	DKLBA78512	DKLBA78645	

(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 (l) 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 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.

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