97-19-18: Auxiliary Power Units

97-19-18 ALLIEDSIGNAL INC.: Amendment 39-10138. Docket 97-ANE-03. Supersedes AD 88-24-07, Amendment 39-6062. \n\n\tApplicability: AlliedSignal Inc. (formerly AiResearch and Garrett) TSCP700-4B and -5 auxiliary power units (APUs), with first stage low pressure compressor (LPC) disks, Part Number (P/N) 3606429-1, installed on but not limited to Airbus A300 series, and McDonnell Douglas DC-10 and KC-10 (military) series aircraft. \n\n\tNote 1: This airworthiness directive (AD) applies to each APU 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 APUs 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 (e) 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. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent first stage LPC disk rim separation due to low cycle fatigue, which could result in an uncontained APU failure and damage to the aircraft, accomplish the following: \n\n\t(a)\tRemove from service first stage LPC disks, P/N 3606429-1, in accordance with the schedule derived from calculations in paragraph C.(3) of AlliedSignal Service Bulletin (SB) No. TSCP700-49-7266, dated June 16, 1996, and the removal procedures described in the Accomplishment Instructions of that SB, and replace with serviceable parts. \n\n\t(b)\tExcept as provided in paragraph (a), this AD establishes a life limit of 8,000 cycles since new (CSN) for first stage LPC disks, P/N 3606429-1. \n\n\t(c)\tThe definition of a disk cycle may be found in the applicable AlliedSignal Inc. APU Component Maintenance Manual. \n\n\t(d)\tExcept as provided in paragraph (e) of this AD, no alternative replacement times may be approved for first stage LPC disks, P/N 3606429-1. \n\n\t(e)\tAn 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, Los Angeles Aircraft 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, Los Angeles Aircraft Certification Office. \n\n\tNote 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles Aircraft Certification Office. \n\n\t(f)\tSpecial 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. \n\n\t(g)\tThe actions required by this AD shall be done in accordance with the following AlliedSignal Inc. SB: \n\n\nDocument No.\nPages\nDate\nTSCP700-49-7266\n1-6\nJune 16, 1996\nTotal pages: 6.\n\n\n\nThis 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 AlliedSignal Aerospace, Attn: Data Distribution, M/S 64-3/2101-201, P.O. Box 29003, Phoenix, AZ 85038-9003; telephone (602) 365-2493, fax (602) 365-5577. 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. \n\n\t(h)\tThis amendment becomes effective on October 27, 1997.