Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Beech Model 400 and 400A airplanes. This proposal would require modification of the autopilot and rudder boost interlock. This proposal is prompted by a report indicating that the rudder boost system installed on these airplanes does not operate correctly during deployment of a thrust reverser. The actions specified by the proposed AD are intended to prevent incorrect operation of the rudder boost system during deployment of a thrust reverser and to prevent the autopilot from exceeding certain bank angle limits; these conditions could result in reduced controllability of the airplane.