Airworthiness Directives; DG Flugzeugbau GmbH, Model DG-500MB Sailplanes

The FAA adopts a new airworthiness directive (AD) for certain DG Flugzeugbau GmbH Model DG-500MB sailplanes. This AD requires you to replace the engine pylon extension/retraction Warner LA10 spindle drive with an improved designed Stross BSA 10 spindle drive and to modify the electrical system following applicable service information. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this AD to prevent failure of the Warner LA10 spindle drive, which could result in failure of the engine pylon extension/retraction mechanism. This condition could cause an unstable engine pylon assembly during flight with loss of control of the sailplane.