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 269/10 Lower Coupling Drive Shaft - Inspection and Replacement Applicability: Model 269A with S/Nos. 0011 to 0314. Model 269A-1 with S/Nos. 0001 to 0007. Model 269B with S/Nos. 0001 to 0079. 4/64 Requirement: 1. Remove the lower coupling drive shaft (P/N 269A5504) and conduct a dye penetrant or magnetic particle inspection of the shaft. Pay particular attention to the radii at the end splines, alignment collar and boot mounting collar. Replace any shaft exhibiting evidence of cracking before further flight. 2. Replace the lower drive shaft coupling P/N 269A5504 with shaft P/N 269A5504-3. 3. Hughes SIN 2A-3, 2A-1-01, 2B-01 and FAA AD 64-6-4 also refer. Compliance: For Para. 1 - At intervals not exceeding 100 hours time in service until the accomplishment of para. 2 above. For Para. 2 - Within 500 hours time in service. The shaft P/N 269A5504 must not exceed 1,500 hours total time in service.