AD 81-18-01 R1 66 FR 63912

This amendment revises an existing airworthiness directive (AD) for Bell Helicopter Textron, Inc. (BHTI) Model 206A, 206B, 206A-1, 206B-1, 206L, and 206L-1 helicopters that currently establishes a retirement life for the main rotor trunnion (trunnion) based on hours time-in-service (TIS). This amendment retains those requirements but revises the AD to remove the trunnion, part number (P/N) 206-011-120- 103, from the applicability. This amendment is prompted by the issuance of another AD for the BHTI Model 206L and 206L-1 helicopters that requires a different method of calculating the retirement life for the trunnions. The actions specified by this AD are intended to prevent failure of the trunnion due to fatigue cracks and subsequent loss of control of the helicopter.