Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires a one-time inspection of the ailerons to determine if certain actions were accomplished previously, and related investigative and corrective actions if necessary. This action is necessary to prevent damage to the rear spar rib-to-rib attachment cleats and the aft rib elements of the fixed tabs of the ailerons. Such damage could lead to reduced structural integrity and consequent failure of the ailerons, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.