COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Piper PA-42 (Cheyenne III) Series Aeroplanes
AD/PA-42/5 Major Structural Fatigue Limitations 4/84
Applicability: All models.
Requirement: 1. Retire the wing main spar lower caps and root fittings and the centre beam assembly from service at or before 18750 hours time in service.
2. Retire the fuselage pressurised cabin at or before 13650 pressure cycles.
Note 1: To avoid confusion, it should be noted that the lower spar cap comprises the complete spar cap assembly including the “T” section element together with the nesting angles and reinforcing strips.
Note 2: On the basis of currently available fatigue substantiating data only one spar cap replacement is permitted. This will allow a once only wing life extension for the aircraft from spar cap replacement after which the airframe in its entirety will be retired.
Effective: Forthwith.
Background: This directive formally promulgates the retirement lives for the above major structural items as determined by full scale fatigue testing.