98-04-39

CCOC Rear Flange

Category - Engine
Effective Date - 02/25/1998
Recurring - No
Supersedes - N/A
Superseded by - N/A
Amendment 39-10351.
Docket 98-ANE-04-AD.

Applicability: Pratt & Whitney (PW) JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR turbofan engines, with combustion chamber outer case (CCOC) part numbers (P/Ns) 490547, 542155, 616315, 728829, 728829-001, 730413, 730413-001, 730414, 730414-001, 767197, 767279, 767279-001 installed. These engines are installed on but not limited to Boeing 737 and 727 series, and McDonnell Douglas DC-9 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 (c) of this AD. The request should include an assessment of the effect 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 uncontained engine failure, inflight engine shutdown, engine cowl release, and airframe damage, accomplish the following:

(a) For engines identified by serial number (S/N) in Table 1 of this AD, perform a one-time borescope inspection of the CCOC rear flange in accordance with paragraph 2.A.(5) of PW Alert Service Bulletin (ASB) No. A6202, Revision 1, dated January 4, 1996, as follows:

                                           Table 1

648796.........653799       655969        665370        674333        695297        702602

648859.........653876       655987        665372        674370        696555        702648

649077.........653904       656036        665382        674513        696573        702699

649135.........654043       656084        665393        674564        696645        702712

649157.........654115       656121        665520        674580        696668        702772

649212.........654428       656948        665529        674611        696757        707158

649262.........654557       656964        665744        687407        700037        707200

649331.........654804       657064        665992        687457        700053        707405

649354.........654860       657119        666004        687634        700103        707922

649406.........654877       657386        666019        687851        700140        708332

649451.........654915       657418        666076        687891        700145        708921

649675.........654949       657584        666331        687893        700156        709002

653316.........654986       657613        666682        688029        700223        709168

653329.........655108       657677        666715        688051        700243        709209

653363.........655310       657739        666948        688054        700248

653495.........655437       665410        667042        688103        700261

653514.........655821       665412        667045        688161        700334

653545.........655842       665461        667059        688470        700383

653574.........655857       665468        667068        688491        700398

653609.........655870       665489        667110        688499        700404

653622.........655898       665497        674193        689934        700665

653789.........655900       665364        674251        695290        700133

(1) For engines installed on McDonnell Douglas DC-9 series aircraft, inspect within 1,000 cycles in service (CIS) since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD 96-23-14, or within 100 CIS after the effective date of this AD, whichever occurs later.

(2) For engines installed on Boeing 737 series aircraft, inspect within 1,500 CIS since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD 96-23-14, or within 100 CIS after the effective date of this AD, whichever occurs later.

(3) For engines installed on Boeing 727 series aircraft, inspect within 2,500 CIS since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD 96-23-14, or within 100 CIS after the effective date of this AD, whichever occurs later.

(b) If the ultrasonic probe assembly, PWA 47942, used to inspect the CCOC rear flange in accordance with AD 96-23-14 was overhauled, repaired, or otherwise altered since original manufacture and not subsequently functionally checked at PW, within 30 days after the effective date of this AD return ultrasonic probes to PW to perform a functional check of the ultrasonic probe assembly.

Note 2: Operators should note that future inspections performed using the probe must be performed with a probe that has passed a functional check at PW since overhaul, repair, or alteration.

(1) If the ultrasonic probe assembly does not pass the functional check, PW must inform the operator, within 24 hours after the probe fails the functional check.

(2) If the ultrasonic probe assembly does not pass the functional check at PW, all engines that were ultrasonically inspected with that probe in accordance with AD 96-23-14 must be borescope inspected in accordance with paragraph 2.A.(5) of PW ASB No. A6202, Revision 1, dated January 4, 1996. Perform the inspections as follows:

(i) For engines installed on McDonnell Douglas DC-9 series aircraft, inspect within 1,000 cycles in service (CIS) since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD 96-23-14, or within 100 CIS after determining the probe is defective, whichever occurs later.

(ii) For engines installed on Boeing 737 series aircraft, inspect within 1,500 CIS since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD 96-23-14, or within 100 CIS after determining the probe is defective, whichever occurs later.

(iii) For engines installed on Boeing 727 series aircraft, inspect within 2,500 CIS since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD 96-23-14, or within 100 CIS after determining the probe is defective, whichever occurs later.

(c) 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.

(d) 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 airplane to a location where the requirements of this AD can be accomplished.

(e) The actions required by this AD shall be done in accordance with the following PW ASB:

Document No.        Pages         Revision         Date
A6202               1-10          1                Jan. 4, 1996
                    11            Original         Feb. 20, 1995
NDIP-835            1-17          A                Oct. 7, 1995
Total pages: 28.

This incorporation by reference of Pratt & Whitney Alert Service Bulletin No. A6202, Revision 1, dated January 4, 1996, was approved previously by the Director of the Federal Register as of January 2, 1997 (61 FR 63707, December 2, 1996). 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 Regional 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.

(f) This amendment becomes effective on February 25, 1998.

FOR FURTHER INFORMATION CONTACT:

Christopher Spinney, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-7175, fax (781) 238-7199.