Boeing 747SP

The Boeing 747SP is a jet airliner, a variant of the Boeing 747. Compared to the original 747, the 747SP has a shortened fuselage. Because of this, it can carry fewer passengers but is able to fly longer distances. The 747SP first flew in 1975 and entered service in 1976. A total of 45 747SPs was built until 1987.
Pan Am and Iran Air both requested an airliner that could fly long range. QANTAS also ordered two 747-SP examples for trans-Pacific routes. One 747SP was modified into the Stratospheric Observatory for Infrared Astronomy (SOFIA). 

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 747SP