The DUKW was designed by Rod Stephens Jr of Sparkman & Stephens Inc. (Yacht Designers), Dennis Puleston, a British Deep Water Sailor & Frank W. Speir, an ROTC Lieutenant at MIT. It was further developed by the National Defence Research Committe & the Office of Scientific Research & Development. At first the military were disdainful of this new vehicle, wondering what possible uses it could have. Then on a stormy day a Coast Guard Cutter got stuck on a Sandbar near Provincetown, Maryland. Quite by chance an experimental DUKW was in the area undergoing trials. It immediately headed to the rescue of the 7 Coastguardsmen stranded on the Cutter and easily battled it's way through 60 knot winds and high seas. The 7 men were rescued and military sceptisism soon evaporated. It would later prove it's seaworthiness by crossing the English Channel The Prototype DUKW was built around a Cab over Engine (COE) version of the standard GMC CCKW 6 wheeled truck. The COE version was the ACKWX with the addition of a watertight hull & propeller. The DUKW was built at the GMC division of General Motors (Called Yellow Truck & Coach before the war). It weighed 7.5 tons, had a 91.5 hp engine, could travel at 6.4 mph in water and 50-55 mph on land. It was also the first vehicle which had variable tire pressure. The Driver could alter the tire pressure from within the vehicle. This proved necessary because a lower tyre pressure was often needed on soft sandy beaches so that it could get a grip without getting stuck. Then the pressure could be increased again for road use. It also had a high output Bilge Pump in case it was holed by enemy fire which could keep it afloat. Not an armoured vehicle, it only had thin metal sheet like a normal truck. Over 21,000 were built and they saw service in the European & Pacific theatres starting with North Africa in late 1942 and then on to the Pacific & the D-Day Landings in June 1944. Because the Allies did not have a port which they could use for the D-Day Landings (Apart from the Mulberry Harbours), DUKW's carried around 18 million tons of supplies to the forces in the beach head. A huge contribution. Many were used in Rescue Roles after the war and there are still lots of them around. Britain's Royal Marines still have some in Scotland for training purposes. Designation DUKW stands for - D = Year designed - 1942 U = Utility (Amphibious) Truck K = All wheel drive W = Both rear axles powered DUKW on the road, With troops & supplies on board, Taking supplies to Soldiers in amphibious mode.