A business jet, private jet, or bizjet is a jet aircraft designed for transporting small groups of people. Business jets may be adapted for other roles, such as the evacuation of casualties or express parcel deliveries, and some are used by public bodies, government officials, VIPs, or the armed forces. History Early developments The first small jet-powered civil aircraft was the Morane-Saulnier MS.760 Paris, developed privately in the early 1950s from the MS.755 Fleuret two-seat jet trainer. First flown in 1954, the MS.760 Paris differs from subsequent business jets in having only four seats arranged in two rows without a center aisle, similar to a light aircraft, under a large sliding canopy similar to that of a fighter. A U.S. type certificate was awarded in July 1958, but commercial sales were limited, with most examples going to the military; an improved civil version similar to a modern very light jet, with a 6-seat enclosed cabin and a conventional door, never proceeded past the prototype stage. The commercial failure of the MS.760 Paris prompted the cancellation of projects by Cessna and Douglas Aircraft to market similar jets. The development of center-aisle cabin business jets was accelerated by an August 1956 United States Air Force (USAF) letter of the requirement for two "off-the-shelf" aircraft: the larger UCX (cargo) and smaller UTX (trainer). These requirements differed from standard Air Force procurement contracts in that there would be no formal competitions, and manufacturers were expected to develop the aircraft without government funds; despite this, a substantial USAF purchase would offset the large investment necessary to develop prototypes. The Lockheed Corporation and McDonnell Aircraft both began the development of UCX aircraft, while North American Aviation pursued the UTX requirement. 1950s first flight The Morane-Saulnier MS.760 Paris had a gross weight of , initially powered by two Turboméca Marboré turbojets of thrust, although most aircraft were later upgraded to units. The aircraft seated a single pilot and up to three passengers under a sliding canopy and was first flown on 29 July 1954. 219 were built. The Lockheed JetStar, designed to meet USAF UCX requirements and seating ten passengers and two crew, first flew on 4 September 1957. A total of 204 aircraft were produced from 1957 to 1978 powered by several different engines; four Pratt & Whitney JT12 turbojets, then Garrett TFE731 turbofans for a MTOW, then two General Electric CF700 turbofans. The smaller, MTOW