What term describes a heavier-than-air aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces and whose free flight does not depend principally on an engine?

• A. Glider
• B. Powered Aircraft
• C. Airplane
• D. Rotorcraft

Answer: (A)

Lift from the wings is what keeps a heavier-than-air aircraft aloft, and a glider is designed to stay airborne primarily on that lift without relying on an engine during normal flight. Gliders are built for high efficiency, with long, slender wings that maximize lift while minimizing drag, so they can glide smoothly and use rising air (thermals, ridge lift) to stay up or gain altitude. They’re launched into the air by another aircraft or a ground-based system and then flown by manipulating the elevator, ailerons, and rudder to maintain control and optimize flight path. This distinguishes them from powered aircraft, which rely on an engine for propulsion, and from rotorcraft, which generate lift with rotating blades.