Airworthiness Directives; Pilatus Britten-Norman Ltd. Models BN- 2, BN-2A, BN-2B, BN-2T, and BN-2A MK. 111 Series Airplanes

This amendment revises airworthiness directive (AD) 84-23-06, which currently requires repetitively inspecting the upper mounting brackets, bolts, and bushings on wing mounted engines for cracks, wear, and insufficient fit on certain Pilatus Britten-Norman Ltd. (Pilatus) Models BN-2, BN-2A, BN-2B, BN-2T, and BN-2A MK. 111 series airplanes, and replacing any cracked, worn, or ill-fitting part. This action retains the same action required in AD 84-23-06, except the action is only applicable to the BN-2A MK. 111 series airplanes. This action is the result of a terminating modification, now available to the Pilatus Models BN-2, BN-2A, BN-2B, BN-2T airplanes, which removes them from the applicability of AD 84-23-06. The actions specified by this AD are intended to prevent failure of the upper mounting brackets on wing mounted engines, which could possibly cause structural failure of the airplane.