COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Boeing 727 Series Aeroplanes AD/B727/20 Thrust Reverser Lockout Actuator Piston - Replacement 2/66 Applicability: All models. Document: Boeing Alert SB No. 78-18. Compliance: Forthwith.