A glider is a plane with no engine that rides on the wind.
Gliders have long, smooth wings to catch rising air. They can stay up for a long time without any engine at all.
More facts about Air Vehicles
Airplanes have big wings that help them stay up in the sky.
Helicopters can go straight up, straight down, and even hover in one spot.
A hot air balloon floats because the warm air inside is lighter than cool air.
Planes have flashing lights so other planes can see them at night.
The Airbus A380 is the biggest passenger plane, with two full floors of seats.