COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Schweizer (Hughes) 269 Series Helicopters AD/HU 269/68 Amdt 1 Lower Pulley Bearings and Housings - Inspection 10/93 Applicability: All model 269A, 269A-1, 269B, 269C and TH-55A helicopters. Requirement: 1. Inspect all lower pulley bearings P/N 269A5050-57 or 269A5050-80 in accordance with Part 1 of Hughes SIN N-146.2 or Part III of Hughes SIN N-164. 2. Retire from service all P/N 269A5050-57 or -80 bearings. 3. For helicopters equipped with sheet metal bearing straps P/N 269A5463, action in accordance with Part 1 of Hughes SIN N-146.2. 4. For helicopters equipped with machined lower pulley bearing caps that are part of a 269A5573-11 "H" frame assembly inspect in accordance with Part 1 of Hughes SIN N-164. Note: FAA AD 80-02-14 refers to initial issue of this directive which referred to -57 bearings only. Compliance: 1. Unless previously actioned in accordance with the requirement document, inspect within 100 hours time in service from 17 September 1993. Thereafter, reinspect all bearings at intervals not exceeding 300 hours time in service. 2. Replace all bearings that have exceeded 1,700 hours time in service within 100 hours time in service from 17 September 1993. Bearings that have not exceeded 1,700 hours time in service by 17 September 1993, must be replaced at 1,800 hours time in service. Thereafter, replace bearings at intervals not exceeding 1,800 hours time in service. 3. Unless previously carried out inspect within 50 hours time in service from 17 September 1993. 4. Unless previously carried out inspect within 50 hours time in service from 17 September 1993. Background: The manufacturer advises that discrepancies in the installation of lower coupling shaft bearings in the "H" frame could have an adverse effect on the life of the bearing. This amendment includes the -80 bearing and adds a repetitive inspection requirement.