COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters AD/HU 369/53 Amdt 2 Main Rotor Drive Shaft 1/91 DM Applicability: All 369 series helicopters equipped with main rotor drive shaft P/N 369D25510. Requirement: Visually inspect the spherical spline and adjacent shaft area of the drive shaft P/N 369D25510. In accordance with Hughes Service Information Notices DN-99, FN-4 or EN-4. Note: FAA AD 81-26-01 R1 Amdt 39-4275 revised by 39-6689 refers. Compliance: Within 300 hours time in service since new or from date of last inspection. Re- inspect at intervals not exceeding 300 hours time in service. Helicopters with shafts that have exceeded 300 hours time in service and were previously exempted from this Directive must be inspected within 25 hours time in service from 7 December 1990. Background: This Directive is further amended to include all 369 models in its applicability.