Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher Model ASK-21 sailplanes that have certain modifications installed. The proposed action would require changing the sailplane flight manual's weight and balance information. 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 the operator from using inaccurate weight and balance information provided in the sailplane flight manual (SFM), which, if not corrected, could lead to hazardous flight conditions.