A sailplane, also known as a glider, is a type of aircraft designed for unpowered flight. It relies on rising air currents, known as thermals, to gain altitude and extend flight duration. Sailplanes are typically lightweight and have long wings, which help them glide efficiently through the air. Pilots of sailplanes often use techniques like soaring to stay aloft for hours, covering long distances without an engine. This makes sailplane flying a popular sport and recreational activity. Organizations such as the Soaring Society of America promote sailplane flying and provide resources for enthusiasts.