COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Robinson R22 Series Helicopters
AD/R22/16
Amdt 4
Lower Actuator Bearing 13/94
Applicability: All series R22 helicopters.
Requirement: Inspect lower bearing assembly P/N A007-3 for fitment of roller bearing assembly P/N A181-4. If the bearing P/N is unknown or if roller bearing assembly P/N A181-4 has not been fitted, action in accordance with Robinson SB 63.
Compliance: Unless previously carried out, within 25 hours time in service from 8 December 1994 or by 31 January 1995, whichever occurs first. Thereafter, reinspect at each maintenance release issue.
Background: Due to the low in-service life of the fan shaft ball bearing the manufacturer has previously introduced a replacement roller bearing. Failure of a fan shaft bearing can resulted in total loss of engine power to the main rotor. This amendment mandates fitment of the roller bearing and a repetitive check to confirm the roller bearing installation after failure of a commercial ball bearing caused a helicopter accident.