What is the difference between a plane and a glider?

Answer 1

A glider is an airplane. The real question is "what is the difference between a powered airplane and a glider?"

Simply put, a powered airplane has a motor and a glider does not. For this reason, powered aircraft are optimized for flight under power. They can take off, climb, and accelerate using their engine.

Gliders, on the other hand, require assistance with launching and gaining altitude. Various systems are used, the most common being aerial towing by a tug aircraft. The glider is towed behind the glider tug (generally a general aviation aircraft, even a crop duster type aircraft, both having extra horsepower to handle the weight of the glider) until the desired altitude and destination are reached, and the glider releases itself from the tow line. Winches and bungees are also used on occasions.

For extended flight, gliders (also called sailplanes) use thermals (updrafts of warm air, much like a circling hawk does), ridge lift (air rising from wind going up a ridge), wave lift (large waves of air coming from a mountain range) and a couple of other ways to be able to maintain altitude.

Gliders differ significantly in design. Their wings are long and slender in order to have less drag. They also are designed to fly slower and far more efficiently than powered aircraft.

Lastly, gliders get one chance at landing. They cannot try again, as they have no way of applying power to abort the landing.