COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Bell Helicopter Textron 212 Series Helicopters
AD/BELL 212/53 Main Rotor Yoke 2/95
Applicability: All Bell 212 model helicopters with Main Rotor Yokes P/N 204-011-102 (all dash numbers) installed.
Requirement: 1. Remove Main Rotor Yoke from the hub assembly. Visually inspect the pillow block bushing holes for corrosion and mechanical damage. Inspect the yoke for cracks in accordance with the BTHI component repair and overhaul manual, using the magnetic particle method.
2. Rework damaged yokes in accordance with the limits of the BTHI component repair and overhaul manual. Remove from service cracked components and components that cannot be reworked within those limits.
Note: FAA AD 93-05-01 refers.
Compliance: 1. Inspect in accordance with Requirement 1 before 1200 hours time in service or within 100 hours time in service after 2 February 1995, whichever occurs later. Re-inspect in accordance with requirement 1 at intervals not to exceed 1200 hours time in service.
2. Rework damaged yokes in accordance with Requirement 2 before further flight.
Background: There have been 12 cracks reported in the main rotor yoke pillow block bushing holes. This AD is intended to detect corrosion and cracking from corrosion pits in the main rotor yoke assembly which could result in failure of the main rotor system and loss of control of the helicopter.