Effective Date - 05/03/1995
Applicability: Allied Signal Aerospace (formerly Garrett Auxiliary Power Division and Garrett Turbine Engine Co.) GTCP85 series auxiliary power units (APU's) with model numbers listed in AlliedSignal Aerospace Service Bulletin (SB) No. GTCP85-49-6919, Revision 1, dated January 15, 1995, except those APU's installed on Boeing 737 and British Aerospace BAC 1-11 series aircraft; and Alert Service Bulletin (ASB) No. GTCP85-49-A6831, Revision 1, dated January 15, 1995, having a one-piece cast turbine rotor with part numbers (P/N) 3842072-1, -2, -3, and P/N 3604604-1, -2, -3, P/N 3606982-1, and P/N 96895-1 through -8. These APU's are installed on but not limited to Boeing 707 series and 727 series aircraft; Lockheed L382 series aircraft; and McDonnell Douglas DC-8-70 series and DC-9/MD-80 series aircraft.
as indicated, unless accomplished previously. To prevent an axially uncontained
APU failure and damage to the aircraft, accomplish the following:
(a) For flight-operable APU's, within 24 months after the effective date of this airworthiness directive (AD), install an exhaust centerbody in accordance with AlliedSignal Aerospace ASB No. GTCP85-49-A6831, Revision 1, dated January 15, 1995, or ASB No. GTCP85-49-A6831, dated March 17,1994; or SB No. GTCP85-49-6919, Revision 1, dated January 15, 1995, or SB No. GTCP85-49-6919, dated May 17, 1994, as applicable.
(b) For APU's that are ground-operable only, within 36 months after the effective date of the AD, install an exhaust centerbody in accordance with AlliedSignal Aerospace SB No. GTCP85-49-6919, Revision 1, dated January 15, 1995, or SB No. GTCP85-49-6919, dated May 17, 1994.
(c) No action is required if the APU is installed on a Boeing 737 or British Aerospace BAC 1-11 series aircraft until the APU is removed and installed on a different type aircraft.
(d) 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: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Los Angeles Aircraft Certification Office.
(e) 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.
(f) The installation of the exhaust center body shall be done in accordance with the following serice documents: Document No. Pages Revision Date ASB No. GTCP85- 49-A6831 Revision Transmittal Sheet 1 1 January 15, 1995 1 1 January 15, 1995 2-5 Original May 17, 1994 6 1 January 15, 1995 7-8 Original May 17, 1994 9-10 1 January 15, 1995 Total pages: 11. SB No. GTCP85-49-6919 1 1 January 15, 1995 2 Original May 17,1994 3 1 January 15, 1995 4 Original May 17,1994 5 1 January 15, 1995 6 Original May 17,1994 7-10 1 January 15, 1995 Total Pages: 10. 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 Services, P.O. Box 52170, Phoenix, AZ 85072-2170, Attn: Dept. 65-71, Mailstop 1802-AA. 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.
(g) This amendment becomes effective on May 3, 1995. FOR FURTHER INFORMATION CONTACT: Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, California 90712-4137; telephone (310) 627-5245; fax (310) 627-5210.