COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Pratt and Whitney Turbine Engines - JT8D Series AD/JT8D/25 Amdt 1 Combustion Chamber Outer Case Incomplete Weld 13/95 Applicability: All JT8D engines with combustion chamber outer case (CCOC), Part Number 796761 or 806675, affected serial numbers as identified in P&W Alert Service Bulletin No 5842, Revision 3, dated October 1990. Requirement: Inspect part number 796761 and 806675 combustion chamber outer cases for cracks or incomplete welds adjacent to the rear flange, in accordance with the requirements of P&W Alert Service Bulletin No 5842, Revision 3, dated October 1990. Note: FAA AD 94-25-07 refers and supersedes FAA AD T89-05-52. Compliance: Effective 7 December 1995: Unless previously accomplished, as detailed in the Requirement Document. Background: The original Directive required inspection of certain JT8D combustion chamber outer cases following advice of the failure of two cases in service. The failures initiated from an area of incomplete weld during manufacture. Undetected cracking of the combustion chamber outer case, could result in an uncontained engine failure. This amendment allows only ultrasonic inspections and supersedes the original AD which allowed visual or fluorescent magnetic penetrant inspections (FMPI) under certain conditions.