Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to Glasflugel Models H301 ``Libelle,'' H301B ``Libelle,'' Standard ``Libelle,'' Standard Libelle 201B, Club Libelle 205, and Kestrel sailplanes. The proposed action would require measuring and adjusting the control surface weight and static moment, and inserting amendments into the maintenance manual. The proposed action results from considerable variation of the weight and static moment of the control surface on the affected sailplanes found during repair or repainting of the control surface. The actions specified by the proposed AD are intended to prevent sailplane flutter because the weight and static moment of the control surface are not within certain limits, which could result in flutter and subsequent loss of control of the sailplane.