Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to Glaser-Dirks Flugzeugbau GmbH (Glaser-Dirks) Model DG-500M gliders. The proposed AD would require installing a rudder gap seal and modifying the cooling liquid reservoir mount. The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by the proposed AD are intended to prevent rudder vibrations caused by flow separation at the rudder gap, which could result in flutter with consequent loss of rudder control.