AD 95-26-03 ACTIVE

This amendment supersedes an existing airworthiness directive (AD), applicable to Pratt & Whitney (PW) JT8D series turbofan engines, that currently requires inspection, and replacement, if necessary, of suspect 7th through 12th stage high pressure compressor (HPC) disks. This amendment adds 46 more applicable engines, revises the inspection requirements, incorporates a new PW Alert Service Bulletin (ASB), and requires reporting the results of the inspection to the manufacturer. This amendment is prompted by the identification of additional suspect engines, by the development of revised inspection intervals, and by the issuance of the new PW ASB. The actions specified by this AD are intended to prevent an uncontained HPC disk failure, which can result in damage to the aircraft.

95-26-03 PRATT & WHITNEY: Amendment 39-9461. Docket 95-ANE-58. Supersedes AD 95-15-51, Amendment 39-9345.
Applicability: Pratt & Whitney (PW) Models JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, -17AR engines with serial numbers specified in Section 2 of PW Alert Service Bulletin (ASB) No. A6226, dated October 17, 1995. These engines are installed on but not limited to Boeing B727 and B737, and McDonnell Douglas DC-9 aircraft. NOTE: 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 use the authority provided in paragraph (c) to request approval from the Federal Aviation Administration (FAA). This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any engine from the applicability of this AD.
Compliance: Required as indicated, unless accomplished previously.
To prevent an uncontained high pressure compressor (HPC) disk failure, which can result in damage to the aircraft, accomplish the following:
(a) Perform a records search, inspect if necessary, repair or replace if necessary, and report results, of stage 7 through 12 HPC disks in accordance with the intervals and procedures of paragraph 2.A through 2.D of PW ASB No. A6226, dated October 17, 1995. Reporting requirements have been approved by the Office of Management and Budget and assigned OMB controlnumber 2120-0056.
(b) For the purpose of this AD, the accomplishment effective date to be used for determination of inspection intervals, as required by Section 2.B of PW ASB A6226, dated October 17, 1995, is defined as the effective date of this AD.
(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. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office.
NOTE: 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 service document:

Document No.
Pages
Revision
Date
PW ASB No. A6626
1-20
Original
October 17, 1995
Total pages: 20.

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, Publications Department, M/S 132-30, 400 Main St., East Hartford, CT 06108. 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.
(f) This amendment becomes effective on January 11, 1996.

On August 15, 1995, the Federal Aviation Administration (FAA) issued airworthiness directive (AD) 95-15-51, Amendment 39-9345 (60 FR 43963, August 24, 1995), applicable to Pratt & Whitney (PW) JT8D series engines with specified serial numbers, to require inspection, and replacement if necessary, of suspect 7th through 12th stage high pressure compressor (HPC) disks. That action was prompted by a report that on June 8, 1995, a PW JT8D-9A engine, installed on a McDonnell Douglas DC-9-32 aircraft, experienced an uncontained engine failure during takeoff at the William B. Hartsfield International Airport in Atlanta, Georgia. The FAA determined that the 7th stage HPC disk failed due to a fatigue crack that originated at a corrosion pit in a shielding hole. The FAA further determined that the fatigue crack origination could have resulted from a disk inspection not performed in accordance with all practices and procedures specified by the FAA and PW. Thisdisk inspection was performed at Turk Hava Yollari (THY), a Turkish engine overhaul and maintenance facility. The FAA identified 24 suspect engines in that AD that had been overhauled by THY for which HPC disk inspection was required. That condition, if not corrected, could result in an uncontained HPC disk failure, which can result in damage to the aircraft.
Since the issuance of that AD, the FAA has identified an additional 46 suspect engines, based on a review of records from the THY facility. In addition, the FAA has also developed revised inspection intervals, based on further examination and analysis of suspect disks. Also, PW has issued Alert Service Bulletin (ASB) No. A6226, dated October 17, 1995. Finally, this superseding AD requires reporting the results of the inspection to the manufacturer. The FAA has reviewed and approved the technical contents of that ASB, which defines inspection requirements of these suspect disks.
Since an unsafe condition has been identified that is likely to exist or develop on other engines of this same type design, this AD supersedes AD 95-15-51 to add 46 more applicable engines, to revise the inspection requirements, to incorporate PW ASB No. A6226, dated October 17, 1995, and to report the results of the inspection to the manufacturer. The actions are 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 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 95-ANE-58." 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 USC 106(g), 40101, 40113, 44701.
39.13 - [AMENDED]
2. Section 39.13 is amended by removing Amendment 39-9345 (60 FR 43963, August 24, 1995), and by adding a new airworthiness directive, Amendment 39-9461, to read as follows:

Submit comments in triplicate to the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, Attention: Rules Docket No. 95-ANE-58, 12 New England Executive Park, Burlington, MA 01803-5299.
The service information referenced in this AD may be obtained from Pratt & Whitney, Publications Department, M/S 132-30, 400 Main St., East Hartford, CT 06108. This information may be examined at the FAA, New England Region, Office of the Assistant Chief Counsel, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Mark A. Rumizen, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (617) 238-7137, fax (617) 238-7199.