Boeing 367-80

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The Boeing 367-80, or "Dash 80" as it was called within Boeing, was an American prototype jet transport built to demonstrate an improved performance over earlier piston-engined airliners like the Model 367.^[1]

Considered to be the prototype for the Boeing 707 airliner, the C-135 (including the best known variant, the KC-135 air tanker used by the United States Air Force) and the Airborne Early Warning series aircraft, the Dash 80 was built in less than two years from project launch in 1952 to rollout on 14 May 1954 for a cost of US$16 million. This was at the time an enormous risk for the Boeing Company, since they had no committed customers for the project.