AD 85-14-02 R2

85-14-02 R2 GARRETT AUXILIARY POWER DIVISION (FORMERLY GARRETT TURBINE ENGINE COMPANY AND THE AIRESEARCH MANUFACTURING COMPANY OF ARIZONA): Amendment 39-5571 as amended by Amendment 39-6115.

Applicability: All GTEC Models GTCP331-200A, -200AC, -200C, -200ER, -250F, -25OH, and -200P Auxiliary Power Units (APU) with fan assembly, Garrett Part Number 3862160-3, -4, or -5, installed; as installed in, but not limited to, Boeing Model 757, and 767 series airplanes, Airbus Model A310 and A300-600 series airplanes, and certain Boeing Model 747 series airplanes with dual units; certificated in any category.

Compliance: Required as indicated, unless already accomplished.

To prevent an uncontained APU cooling fan failure, accomplish the following:

A. Upon removal of the cooling fan assembly, Garrett Part Number 3862160-3 or -4, from an affected GTCP331 series Auxiliary Power Unit (APU) for any reason; or within 1,000 airplane hours time-in-service after August 15, 1985, or prior to September 15, 1985, whichever comes first, for the Boeing Model 757 and 767 series airplanes; and within 1,000 airplane hours time-in-service after April 2, 1987 (the effective date of Amendment 39-5571), for all other airplanes with a GTCP331 series APU installed; incorporate the new fan assembly with the improved fan containment housing as specified in Section 2.A, "Accomplishment Instructions," of Garrett Service Bulletin GTCP331-49-5546, dated August 9, 1984.

B. Upon removal of the modified cooling fan assembly, Garrett Part Number 3862160-5, from an affected GTCP331 series APU for any reason, or within six (6) months after the effective date of this AD, whichever occurs first, for all airplanes with GTCP331 series APU installed, incorporate the latest improved fan containment configuration in accordance with the Accomplishment Instructions of Garrett Service Bulletin 3862160-49-5716, dated November 19, 1987.

C. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may add any comments and then send it to the Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.

D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a maintenance base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to the Garrett Airline Service Division, A Division of the Allied-Signal Aerospace Company, Technical Publications, Dept. 65-70, P.O. Box 29003, Phoenix, Arizona 85038. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or at 3229 East Spring Street, Long Beach, California.

Airworthiness Directive 85-14-02, effective August 15, 1985, was revised by Amendment 39-5571 (AD 85-14-02 R1) which was effective April 2, 1987.

This amendment (39-6115, AD 85-14-02 R2) becomes effective February 22, 1989.