Airworthiness Directives; Kaman Aerospace Corporation Model K-1200 Helicopters

This amendment revises an existing airworthiness directive (AD) for Kaman Aerospace Corporation (Kaman) Model K-1200 helicopters that currently requires reducing the life limit of the rotor shaft and teeter pin assembly and establishing a life limit for the flap clevis. This amendment retains those requirements but removes a flap clevis part number from the applicability and, as a result of a comment, changes the application of the life limit from the flap clevis to the flap clevis assembly. This amendment is prompted by the determination after an analysis of testing results that a certain flap clevis assembly should have an unlimited life. The actions specified by this revision are intended to remove the life limit for a specified flap clevis assembly. The actions specified by this AD are intended to prevent fatigue failure of the rotor shaft, teeter pin assembly, and flap clevis assembly, and subsequent loss of control of the helicopter.