sentences:  This folding mechanism has the advantage of simplicity, but it means that the engine can not be windmill-started if the battery is flat.Because of the forward pointing blades when the engine is off, the Carat cannot be towed aloft like traditional sailplanes.The first flight was made on 16 December 1997 and the first production model displayed at Aero '99 at Friedrichshafen in April 1999 as the Technoflug TFK-2 Carat.