In 1948, six Boeing engineers worked for weekend in a hotel room to produce a 33 page proposal, which included moving from turbo-prop to jet engines, and accompanied this proposal with a balsa-model prototype, in order to salvage a team project that was at the risk of failure.

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Their engines are jet turbines that use the jet's thrust to spin a prop.

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Large flaps move out and down, placing the jet on a landing path at speeds similar to those of piston prop jobs.

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