Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to certain Alexander Schleicher Segelflugzeugbau (Schleicher) Models ASW-19 and ASK-21 sailplanes. The proposed AD would require: modifying the rudder surface panels; replacing the airbrake bellcrank; and modifying the rear canopy hinge structure. 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 loss of the canopy caused by design deficiency, airbrake failure caused by cracking, and rudder panel flutter caused by high density altitude conditions, all of which, if not corrected, could result in reduced sailplane controllability.