Turbine Wheel By P/N
Effective Date - 03/24/1997
Applicability: AlliedSignal Inc. (formerly Garrett Auxiliary Power Division) GTCP85 series auxiliary power units (APUs), incorporating a one-piece cast turbine wheel, Part Numbers (P/Ns) 968095-X, 3604604-X, 3606982-1, or 3842072-X (where "X" denotes any number). These APUs are installed on but not limited to the following aircraft: British Aerospace BAC 1-11 series; Boeing 707, 727, and 737 series; Lockheed L382 series; and McDonnell Douglas DC-8-70, DC-9, and MD-88 series aircraft.
Note 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 (c) 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 turbine shroud fragments from exiting the APU and puncturing the APU compartment, which could result in reduced fire extinguishing capability in the APU compartment, accomplish the following:
(a) For flight operable
APUs, within 24 months after the effective date of this AD, accomplish
either of the following:
(b) For APUs that
are operable on the ground only, within 36 months after the effective
date of this AD, accomplish either of the following:
(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, Los Angeles Aircraft 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, Los Angeles Aircraft Certification Office.
Note 2: Information concerning the existence of approved alternative method of compliance with this AD, if any, may be obtained from the Los Angeles Aircraft 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 ASBs:
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 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. (f) This amendment becomes effective on March 24, 1997. FOR FURTHER INFORMATION CONTACT: Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone (310) 627-5245; fax (310) 627-5210.