Airworthiness Directives; Grob-Werke Gmbh & Co KG Models G102 CLUB ASTIR III, G102 CLUB ASTIR IIIb, and G102 STANDARD ASTIR III Sailplanes

The FAA supersedes Airworthiness Directive (AD) 2001-26-25, which applies to all Grob-Werke Gmbh & Co KG (Grob) Models G102 CLUB ASTIR III, G102 CLUB ASTIR IIIb, and G102 STANDARD ASTIR III sailplanes. AD 2001-26-25 currently requires you to apply a red mark and install a placard on the airspeed indicator to restrict the Vne airspeed. This AD requires you to install additional mass balance in the elevator and ailerons and determine resultant empty weight and empty weight center of gravity; incorporate a revision in the sailplane maintenance manual; and remove the red mark and the red placard on the airspeed indicator (both required by AD 2001-26-25). 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 elevator flutter, which could cause structural damage. Such damage could result in loss of control of the sailplane.