Airworthiness Directives; Glaser-Dirks Flugzeugbau GmbH Model DG- 400 Gliders'

This amendment adopts a new airworthiness directive (AD) that applies to certain Glaser-Dirks Flugzeugbau GmbH (Glaser-Dirks) Model DG-400 gliders. This AD requires inspecting the powerplant mount and the propeller mount for any loose parts. This AD also requires modifying the starter motor, retrofitting the holder for the starter motor, and checking the engine ignition timing; either immediately or at a certain time depending on the results of the inspection. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by this AD are intended to prevent damage to the engine caused by vibration, which could result in loss of engine power during critical phases of flight.