It was developed by SNCASE in the early 1950s, and made its maiden flight on 27 May 1955. It include some de Havilland designs and components developed for the de Havilland Comet. SNCASE was then merged into the larger Sud Aviation conglomerate before the aircraft entered revenue service on 26 April 1959 with Scandinavian Airlines System (SAS). Until the production end in 1972, 282 have been built. It was operated in every continent until its retirement in 2005. The short-range, five-abreast airliner is powered by two aft-mounted Rolls-Royce Avon turbojet engines, allowing a clean low wing. The configuration was later retained in many narrow-body aircraft and regional jets. The initial I, III and VI variants could seat 90 to 99 passengers over 1,650 to 2,500 km (890 to 1,350 nmi). The later, slightly longer 10/11 variants could seat 99 to 118 passengers over 2,800 to 3,300 km (1,500 to 1,800 nmi), powered by Pratt & Whitney JT8D low-bypass turbofans. The stretched Caravelle 12 could seat 131 over 3,200 km (1,700 nmi). The Caravelle belongs to the first generation of passenger aircraft to use newly developed jet propulsion technology, and it was the first jet airliner developed specifically for the short/medium-range sector of the market. Early in the Caravelle's career, its chief competitors were propeller-driven aircraft, such as the British-built Vickers Viscount and the U.S.-built Convair CV-440. Reportedly, the Caravelle proved to be a highly reliable airliner during its early years of service. The low accident rate for the type led to lower than average insurance premiums for Caravelle operators. The Caravelle was typically powered by a pair of British-built Rolls-Royce Avon turbojet engines, installed in a rear-mounted position close to the tail unit. Various models of the Avon engine were adopted for different versions of the airliner, often with increased thrust and additional features such as thrust reversers. Alternative powerplants were adopted or proposed for some Caravelle models, such as the U.S.-built Pratt & Whitney JT8D-1 and General Electric CJ-805-23C engines. Variants. For more details of the variants, click here. For more details of the development and design, click here. The specifications below are for the Caravelle 12 (Super Caravelle) variant.