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 369/81 Tail Rotor Swashplate Bearing Set 8/90 DM Applicability: All model 369D, 369E and 369F/FF series helicopters. Requirement: Action in accordance with McDonnell Douglas SIN DN-167, EN-58 or FN-46 as applicable. Compliance: Part 1 of Requirement document-Prior to further flight after 30 June 1990. If bearing seals are green or yellow a certification which includes the bearing seal colour and a statement of compliance with this AD shall be entered on the Maintenance Release. Note: This inspection may be accomplished by the pilot in command. Part 2 of Requirement document-Within 10 hours time in service for applicable black seal bearing set and thereafter at intervals not exceeding 10 hours time in service. Replace bearing set before 300 hours time in service. Bearing sets that have exceeded 300 hours time in service by 30 June 1990 must be replaced before further flight. Background: Inspection for defective tail rotor swashplate bearing sets is required to prevent failure of the bearing which could result in loss of control of the helicopter.