Airliner variants

Some variants of airliners have been developed for carrying freight or for luxury corporate use. Many airliners have also been modified for government use as VIP transports and for military functions such as airborne tankers (for example, the Vickers VC10, Lockheed L1011, Boeing 707), air ambulance (USAF/USN McDonnell Douglas DC-9), reconnaissance (Embraer ERJ 145, Saab 340, Boeing 737), as well as for troop-carrying roles. Business jet, private jet, or bizjet, is a term describing a jet aircraft, usually of smaller size, designed for transporting groups of up to 19 individuals. 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 or the armed forces. The more formal terms of corporate jet, executive jet, VIP transport or business jet tend to be used by the firms that build, sell, buy and charter these aircraft. The Boeing 707 is a mid-size, narrow-body four-engine jet airliner built by Boeing Commercial Airplanes from 1958 to 1979. Its name is commonly pronounced as "Seven Oh Seven". Versions of the aircraft have a capacity from 140 to 189 passengers[4] and a range of 2,500 to 5,750 nautical miles (4,600 to 10,650 km).[5] Developed as Boeing's first jet airliner, the 707 is a swept-wing design with podded engines. Dominating passenger air transport in the 1960s and remaining common through the 1970s, the 707 is generally credited with ushering in the Jet Age.[6][7] The 707 was the third jetliner in service, but was the first to be commercially successful. It established Boeing as one of the largest manufacturers of passenger aircraft, and led to the later series of airliners with "7x7" designations. The later 727, 737, and 757 share elements of the 707's fuselage design. The 707 was developed from the Boeing 367-80, a prototype jet first flown in 1954. A larger fuselage cross-section and other modifications resulted in the initial production 707-120, powered by Pratt & Whitney JT3C turbojet engines, which first flew on December 20, 1957. Pan American World Airways began regular 707 service on October 26, 1958. Later derivatives included the shortened long-range 707-138 and the stretched 707-320, both of which entered service in 1959. A smaller short-range variant, the 720, was introduced in 1960. The 707-420, a version of the stretched 707 with Rolls-Royce Conway 508 turbofans, debuted in 1960, while Pratt & Whitney JT3D turbofans debuted on the 707-120B and 707-320B models in 1961 and 1962, respectively. The 707 has been used on domestic, transcontinental and transatlantic flights, and for cargo and military applications. A convertible passenger-freighter model, the 707-320C, entered service in 1963, and passenger 707s have been modified to freighter configurations. Military derivatives include the E-3 Sentry airborne reconnaissance aircraft and the C-137 Stratoliner VIP transports. Boeing produced and delivered 1,011 airliners including the smaller 720 series; over 800 military versions were also produced. As of August 2011, 10 Boeing 707s were in airline service.[8] By August 2012, this number was down to two both in Iran.