Airworthiness Directives; BFGoodrich Avionics Systems, Inc. SKYWATCH SKY497 Installations with a Top-Mounted Antenna

This amendment adopts a new airworthiness directive (AD) that applies to all BFGoodrich Avionics Systems, Inc. (BFGoodrich) SKYWATCH SKY497 installations with a top-mounted antenna that are installed on aircraft. This AD requires incorporating information into the airplane flight manual (AFM) that specifies verifying the correct antenna configuration each time an aircraft equipped with a SKY497 installation with a top-mounted antenna is powered-up. The AD also requires removing from service any of these SKY497 installations with an incorrect antenna configuration. This AD results from numerous reports of internal component failure of the above-referenced installations, which changed the antenna configuration (from TOP to BOTTOM mount). The actions specified by this AD are intended to prevent the display of target indicators on the wrong side of the aircraft caused by an internal component failure in the SKY497 installations with a top- mounted antenna, which could result in the pilot making an incorrect initial maneuver based on the displayed information while trying to visually acquire the aircraft.