COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series AD/TPE 331/40 Scavenge Oil Pump Assembly 6/89 Applicability: TPE 331-25; -43; -47; -55; -61; -1; -2; -3; -5; -6; -8; -10 and -11 series turbo prop and TSE 331-3U turbo shaft engines. Requirement: Inspect and modify applicable engines in accordance with Garrett (Allied Signals) Service Bulletin TPE 331-72-0533 Revision 2. Note: FAA AD 89-07-07 Amdt 39-6140 refers. Compliance: Unless already accomplished; at next access to affected parts, or within 1800 hours time in service after 15 June 1989 or prior to further operation after 1 January 1991 whichever is the sooner. Background: This Directive is issued to prevent turbine failure. There have been several instances of severe erosion and/or fracture of the berryllium copper main shaft nut. SOAP sampling for berryllium has not been completely effective in detecting nut erosion (cancelled AD/TPE 331/34 refers). SB TPE 331-72-0533 Rev 2 embodies an oil scavenge pump with improved outlet port which reduces pump susceptibility to nut erosion.