TRNS

The DUKW was designed by Rod Stephens, Jr. of Sparkman & Stephens, Inc. yacht designers, Dennis Puleston, a British deep water sailor resident in the U.S., and Frank W. Speir, a Reserve Officers Training Corps Lieutenant out of Massachusetts Institute of Technology.[8] Developed by the National Defense Research Committee and the Office of Scientific Research and Development, it was initially rejected by the armed services. When a United States Coast Guard patrol craft ran aground on a sand bar near Provincetown, Massachusetts, an experimental DUKW happened to be in the area for a demonstration. Winds up to 60 knots (110 km/h), rain, and heavy surf prevented conventional craft from rescuing the seven stranded Coast Guardsmen, but the DUKW had no trouble, and the military opposition melted. The DUKW would later prove its seaworthiness by crossing the English Channel.

The DUKW prototype was built around the GMC ACKWX, a cab-over-engine (COE) version of the GMC CCKW six-wheel-drive military truck, with the addition of a watertight hull and a propeller. The final production design, perfected by a few engineers at Yellow Truck & Coach in Pontiac, Michigan, was based on the CCKW. The vehicle was built by the GMC division of General Motors, which was still called Yellow Truck and Coach at the beginning of the war. It was powered by a Chevrolet straight-6 engine of 270 in³ (4.416 L).