747SP

Boeing 747SP
Boeing 747SP of launch customer Pan Am at London Heathrow Airport in 1978
Role	Wide-body jet aircraft
Manufacturer	Boeing Airplane Company
First flight	July 4, 1975
Introduction	1976 with Pan Am
Status	In limited service as governmental, charter or VIP aircraft, one in service as SOFIA.
Primary users	Pan Am (historical) United Airlines (historical) South African Airways (historical) Iran Air (historical)
Produced	1976–1989
Number built	45
Developed from	Boeing 747-100
Variants	SOFIA

The Boeing 747SP is a modified version of the Boeing 747 jet airliner which was designed for ultra-long-range flights. The SP stands for "Special Performance". The 747SP is similar to the 747-100 except for the shortened fuselage, larger tailplane, and simplified trailing edge flaps. The weight saved by the shorter fuselage permits longer range and increased speed relative to other 747 configurations.

Known during development as the short-body 747SB, the 747SP was designed to meet a 1973 joint request from Pan American World Airways and Iran Air, who were looking for a high-capacity airliner with sufficient range to cover Pan Am's New York–Middle Eastern routes and Iran Air's planned Tehran–New York route. The aircraft also was intended to provide Boeing with a mid-size wide-body airliner to compete with existing trijet airliners.

The 747SP first entered service with Pan Am in 1976. The aircraft was later acquired by VIP and government customers. While in service, the 747SP set several aeronautical performance records, but sales did not meet the expected 200 units, and production ultimately totaled 45 aircraft.

The idea for the 747SP came from a request by Pan Am for a 747 variant capable of carrying a full payload non-stop on its longest route between New York and Tehran. Joined with Pan Am's request was Iran Air; their joint interest was for a high capacity airliner capable of covering Pan Am's New York–Middle Eastern routes and Iran Air's planned New York-Tehran route. (New York to Tehran may have been the longest non-stop commercial flight in the world for a short time, until Pan Am started Tehran to New York in mid-1976.) The aircraft was launched with Pan Am's first order in 1973 and the first example delivered in 1976.

A shorter derivative of the 747-100, the SP was developed to target two market requirements. The first was a need to compete with the DC-10 and L-1011 while maintaining commonality with the 747, which in its standard form was too large for many routes. Until the arrival of the 767, Boeing lacked a mid-sized wide-body to compete in this segment. The second market requirement was an aircraft suitable for the ultra-long-range routes emerging in the mid-1970s following the joint request. These routes needed not only longer range, but also higher cruising speeds. Boeing could not afford to develop an all-new design, instead opting to shorten the 747 and optimize it for speed and range, at the expense of capacity.

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