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catapult(kăt`əpŭlt'), mechanism used to throw missiles in ancient and medieval warfare. At first, catapults were specifically designed to shoot spears or other missiles at a low trajectory (see bow and arrowbow and arrow,
weapon consisting of two parts; the bow is made of a strip of flexible material, such as wood, with a cord linking the two ends of the strip to form a tension from which is propelled the arrow; the arrow is a straight shaft with a sharp point on one end and
..... Click the link for more information. ). They were originally distinguished from ballistae and trebuchets, both of which were large military engines used to hurl stones and other missiles, but these distinctions later blurred. Later, larger catapults mounted on a single arm also hurled stones, pots of boiling oil, and incendiaries at a high trajectory. They were used to attack or defend fortificationsfortification,
system of defense structures for protection from enemy attacks. Fortification developed along two general lines: permanent sites built in peacetime, and emplacements and obstacles hastily constructed in the field in time of war.
..... Click the link for more information. . Catapults were widely employed in siegesiege,
assault against a city or fortress with the purpose of capturing it. The history of siegecraft parallels the development of fortification and, later, artillery. In early times battering rams and bores were employed to break down the walls and gates of a fortified place
..... Click the link for more information. warfare, but with the introduction of artilleryartillery,
originally meant any large weaponry (including such ancient engines of war as catapults and battering rams) or war material, but later applied only to heavy firearms as opposed to small arms.
..... Click the link for more information. they passed from use. In the 20th cent. catapults using hydraulic pressure were reintroduced to launch aircraft from warships.
(1) In military terminology a throwing machine activated by the elastic force of twisted cords made from sinews, hair, and so forth. Catapults were used in ancient Greece and Rome up to the end of the fifth century mainly for besieging fortresses; lightweight versions (from the fourth century B.C.) were also used in field combat. Catapults hurled stones, logs, barrels with burning tar, and other objects over distances of a few hundred meters and lances up to 185 cm long and weighing up to 1.5 kg over distances up to 150 m.
(2) A device for imparting initial (launch) velocity to airplanes, gliders, and so forth on a short runway. A catapult consists of a driving apparatus (trolley, “shuttle”, hook, etc.), a guiding device (usually rails), and a launching mechanism. The driving apparatus with the aircraft attached to it is accelerated either by a jet engine or by employing the energy of steam, gunpowder, compressed air, springs, or rubber bands. Toward the end of the takeoff run, the driving mechanism is abruptly halted, and the aircraft separates from the driving apparatus with the necessary velocity for independent flight.
Catapults with horizontal guiding devices are employed mainly on aircraft carriers, where steam catapults are usually employed that provide an airplane acceleration on a runway of 60–80 m up to a velocity of 200–300 km/hr. Catapults with vertical guiding devices are used for practicing ejection from airplanes on the ground, training flight crews, and studying the effects of great strains on man over short time periods.
REFERENCEKorotkin, I. M., Z. F. Slepenkov, and B. A. Kolyzaev. Avianostsy. Moscow. 1964.
G. M. BADAEV and E. P. GOLUBKOV