The force of gravity pulls everything down towards the earth, however there are many machines designed to overcome the force of gravity ranging from toy helicopters and planes, hot air balloons, drones, fighter jet planes to sophisticated satellites and space shuttles . The mechanism and design used by these machines to fly in air , defying the force of gravity varies . More information on the design and companies manufacturing different types of aircraft , why india is not able to develop any aircraft, and has to import from small countries like France, Italy