65-09-03 GRUMMAN: Amdt. 39-57 Part 39 Federal Register April 21, 1965. Applies to Model G-159 Aircraft Equipped with AiResearch Gas Turbine Compressor Units Model GTC 85-37, Series 1 through 18.
Unless already accomplished within the last 235 hours of APU operation or 470 starts of the APU prior to the effective date of this AD, accomplish the following within the next 15 hours of APU operation or 30 starts of the APU, whichever occurs first, and at intervals not to exceed 250 hours of APU operation or 500 starts of the APU since the last inspection:
(a) Visually inspect in accordance with Grumman Gulfstream Customer Bulletin No. 180, dated February 12, 1965, or later FAA-approved revision, and AiResearch Service Bulletin No. 49-1045, Revision 1, dated January 29, 1965, or later FAA-approved revision, the APU turbine wheel and exducer for surface cracks, the shroud plate for indications of rubbing, and the blade tips for indications of erosion and over-heating. Remove fromservice any turbine wheel and any exducer found cracked, or having rubbed, eroded, or over-heated blades.
(b) Check and adjust as necessary the starter clutch for proper torque value in accordance with Grumman Gulfstream Customer Bulletin No. 179, dated January 8, 1965, or later FAA-approved revision, and AiResearch Service Bulletin No. 49-1042, dated November 13, 1964, or later FAA-approved revision.
(c) Check and adjust as necessary the APU fuel pump acceleration limiter for proper setting in accordance with AiResearch Service Bulletin No. 49-1045, Revision 1, dated January 29, 1965, or later FAA-approved revision.
This directive effective April 21, 1965.