COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Sikorsky S-76 Series Helicopters
AD/S-76/58 Tail Gearbox Output Shaft 5/92
Applicability: All model S76A, S76B and S76C helicopters up to and including S/N 760390. Requirement: Action in accordance with Sikorsky Alert Service Bulletin No 76-66-27.
Compliance: Within 150 hours time in service from 30 April 1992 or by 30 August 1992, whichever occurs first.
Background: The manufacturer requires a one-time inspection of the tail rotor gearbox output shaft assembly internal bore for a surface irregularity/groove. Scoring in the bore area may initiate a premature fatigue failure.