AD 98-04-39

This amendment adopts a new airworthiness directive (AD) that is applicable to Pratt & Whitney (PW) JT8D series turbofan engines. This action requires a one-time borescope inspection of the combustion chamber outer case (CCOC) for cracks on engines identified by serial number that were ultrasonically inspected in accordance with AD 96-23-14 with defective probes. In addition, this AD requires an ultrasonic probe functional check at PW prior to using the probe to perform an ultrasonic inspection if the probe was overhauled, repaired, or otherwise altered since original manufacture and not subsequently functionally checked by PW. This amendment is prompted by reports of defective probes discovered in the field. The actions specified in this AD are intended to prevent uncontained engine failure, inflight engine shutdown, engine cowl release, and airframe damage.
The incorporation by reference of Pratt & Whitney Alert Service Bulletin No. A6202,
Revision 1, dated January 4, 1996, as listed in the regulations, was approved previously by the
Director of the Federal Register as of January 2, 1997 (61 FR 63707, December 2, 1996).
Comments for inclusion in the Rules Docket must be received on or before April 27 1998.

Final rule; request for comments.

98-04-39 Pratt & Whitney: 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) ofthis 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 installedon 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 manufactureand 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 aircraft 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
January 4, 1996

11
Original
February 20, 1995
NDIP-835
1-17
A
October 7, 1995
Total pages: 28.

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 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.

On November 7, 1996, the Federal Aviation Administration (FAA) issued airworthiness directive (AD) 96-23-14, Amendment 39-9820 (61 FR 63707, December 2, 1996), which supersedes ADs 87-11-07 R1 and 95-08-15, to require repetitive eddy current, fluorescent penetrant, fluorescent magnetic particle, or visual inspections for cracks in the rear flange, and ultrasonic, fluorescent penetrant, or fluorescent magnetic particle inspections for cracks in the PS4 boss, and drain bosses of the combustion chamber outer case (CCOC); and an additional inspection of the CCOC rear flange for intergranular cracking. In addition, AD 96-23-14 reduces the rear flange inspection interval for CCOCs when only the aft face of the rear flange has been inspected, and introduces an improved ultrasonic probe assembly. Also, AD 96-23-14 introduces a rotating eddy current probe for shop inspections in which the case is removed from the engine. Finally, AD 96-23-14 eliminates fluorescentpenetrant inspection (FPI), fluorescent magnetic particle inspection (FMPI), and visual inspections from hot section disassembly level inspection procedures. That action was prompted by reports of crack origins in the forward face of the rear flange that could not be detected by the inspection methods for installed CCOCs that were mandated in the superseded ADs 87-11-07 R1 and 95-08-15. That condition, if not corrected, could result in uncontained engine failure, inflight engine shutdown, engine cowl release, and airframe damage.
Since the issuance of AD 96-23-14, the FAA has received reports of 13 defective ultrasonic inspection probes used to accomplish the ultrasonic inspections required by AD 96-23-14. Those 13 defective probes have been identified and removed from the field, but the engines inspected with the defective probes must be reinspected. Other ultrasonic inspection probes were either overhauled, repaired, or otherwise altered since original manufacture and were not subsequently functionally checked to insure that they met the necessary inspection sensitivity requirements. The calibration check contained in the ultrasonic inspection procedure does not serve as an adequate check to insure that the probe meets inspection sensitivity requirements. Currently, only PW has the capability to perform the necessary functional check to the proper standard.
The FAA has reviewed and approved the technical contents of PW Alert Service Bulletin (ASB) No. A6202, Revision 1, dated January 4, 1996, that describes procedures for a borescope inspection of the CCOC rear flange for cracks. This ASB identifies applicability to engines installed on McDonnell Douglas DC-9 and Boeing 737 series engines only; however, the inspection requirements of paragraph 2.A.(5) of PW ASB No. A6202, Revision 1, dated January 4, 1996, are applicable to engines installed on Boeing 727 series aircraft as well.
Since an unsafe condition has been identified that is likely to exist or develop on other engines of the same type design, this AD is being issued to prevent an uncontained engine failure. This AD requires a borescope inspection of engines, identified by serial number (S/N) that were ultrasonically inspected in accordance with AD 96-23-14 with defective probes. In addition, this AD requires a functional check at PW of all ultrasonic inspection probes that were overhauled, repaired, or otherwise altered since original manufacture and not subsequently functionally checked. The borescope inspection is required to be accomplished in accordance with the ASB 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 safetyand, 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 98-ANE-04-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 regulationis 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) asfollows: 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: