Catapult

A mechanism used to hurl, or launch, an object at a high rate of speed. catapults are used to launch heavily loaded aircraft from the decks of aircraft carriers.
An aircraft catapult is a device used to launch aircraft from ships, most commonly used on aircraft carriers, as a form of assisted take off. It consists of a track built into the flight deck, below which is a large piston or shuttle that is attached through the track to the nose gear of the aircraft, or in some cases a wire rope, called a catapult bridle, is attached to the aircraft and the catapult shuttle. Different means have been used to propel the catapult, such as weight and derrick, gunpowder, flywheel, air pressure, hydraulic, and steam power. The producers are developing the use of Electromagnetic Aircraft Launch Systems with the construction of the new aircraft carriers.