AD 80-08-12

80-08-12 PRATT & WHITNEY AIRCRAFT OF CANADA, LIMITED: Amendment 39-3748. Applies to Pratt & Whitney Aircraft of Canada, Limited PT6A-6, -6A, -6B, -6/C20, -11, -15AG, -20, -20A, -20B, -21, -25, -25A, -27, -28, -34, -34B, -34AG, -36, -41, -45A, -45B, -112, -135 turboprop engines and Pratt & Whitney Aircraft PT6A-20A, -25, -27, -28, -34 turboprop engines incorporating Part Number 02-14910-01 fuel pump coupling. Compliance required as indicated unless previously accomplished. To preclude wear of the fuel pump drive coupling splines which results in an engine flameout condition, accomplish the following: a. Within the next 50 hours in service after the effective date of this AD for engines which have had a fuel pump removed within the last 200 hours in service, inspect 02-14910-01 fuel pump drive coupling for wear or damage. If the fuel pump drive coupling is worn or damaged replace the fuel pump drive coupling with a new coupling with the same part number or 5006050 coupling assembly in accordance with Paragraph 2, Accomplishment Instructions, in Pratt & Whitney Aircraft of Canada, Limited Service Bulletin Nos. 1316, 3139 or 12025 as applicable or an approved equivalent inspection and parts. If 02-14910-01 coupling is installed repeat above inspection each 200 hours in service thereafter until Paragraph b is accomplished. b. For all engines, prior to July 1, 1981, replace 02-14910-01 fuel pump drive coupling with 5006050 coupling assembly in accordance with Paragraph 2, Accomplishment Instructions in Pratt & Whitney Aircraft of Canada, Limited Service Bulletin Nos. 1316, 3139 or 12025 as applicable or approved equivalent inspection and parts. When 5006050 coupling assembly is installed, the inspection requirements of this AD no longer apply. Aircraft may be flown to a base for performance of maintenance required by this AD per FAR 21.197 or FAR 21.199. All equivalent inspections and parts must be approved by the Chief, Engineering & Manufacturing Branch, of the Eastern Region of the FAA. (Pratt & Whitney Aircraft of Canada, Limited Service Bulletin Nos. 1316, 3139 or 12025 pertain to this subject.) This amendment is effective April 18, 1980.