The Boeing 747SP was built as a stocky version of the original 747-100, with a shortened fuselage, larger tailplane and modified trailing edge flaps. The weight saved by the shorter fuselage allowed longer flights at higher speeds, but capacity was decreased. The fuselage was shortened 48 ft. 4 in. After removing fuselage sections in front and behind the wings, lighter wing material, new flap design, and removal of underwing flap housings, the final weight reduction was 45,000 lbs. less than a 747-200.
The name was originally the 747SB, which meant short body, but was changed to Special Performance, as it was designed to meet a request from Pan Am and Iran Air for a high-capacity airliner with sufficient range to cover Pan Am’s New York-Middle East routes and Iran Air’s planned Tehran-New York route. The four-engine 747SP was competing with the Lockheed L-1011 and the McDonnell Douglas DC-10, both trijets.
The first 747SP rolled out on May 19, 1975, and its first flight took place on July 4 of that year. Pan Am was the launch customer and took its first delivery on March 5, 1976. The airline placed an initial order for 10, with options for 15, but ended up not exercising the options. The order at the time was valued at $280 million.
Boeing had set a production total for the SP at 200, but it only produced 45 by the end of its cycle in 1989.
There are a handful of 747SPs still in commercial service, all in the Middle East.