At its core, a plane without an engine relies on aerodynamic lift and energy management rather than thrust to stay airborne. This covers several distinct aircraft types, including sailplanes, hang gliders, paragliders, and powered parachutes that may use small engines or rely solely on gravity and rising air. Lift is generated by wings shaped to create pressure differences, while forward speed comes from either a tow launch, winch, cable break, or existing momentum. Pilots manage energy by trading altitude for speed and using up-currents to gain height, enabling sustained flight without combustion. Below are the key configurations and how each accomplishes controlled, engine-free flight.
