From http://www.globalsecurity.org/military/systems/ground/dukw.htm

DUKW

The DUKW was an amphibious version of the 2-1/2 ton General Motors cargo truck. It was developed by the US Army during World War II as a means to deliver cargo from ships at sea, directly to shore. Ultimately DUKW was a vital factor in landings in the Pacific, in Africa, and on the beaches of Normandy. In early 1942, ships sat waiting to discharge cargo at foreign ports, sometimes for months, due to lack of port facilities. Ships waited for barges, barges waited for trucks, and trucks waited for trains. Smaller landing craft were being built by the hundreds as quickly as possible to accomplish this mission. Planners soon found the need to deliver high priority cargo, such as ammunition and water, directly to troops fighting inland off the invasion beaches.

The government assigned the task of developing this new type of landing craft to the National Defense Research Committee (NDRC). Of all of the scientific and technical projects undertaken by the National Defense Research Committee and the Office of Scientific Research and Development, the story of the DUKW (pronounced duck) is perhaps the most interesting example of the resistance to new technologies. Its introduction and deployment required an uphill battle by civilian scientists but demonstrated the stunning successes achieved when the military finally listened.

Composed of engineers, designers, technicians and entrepreneurs, the first mission of this group was to develop an amphibious version of the 1/4-ton Jeep. The first amphibious vehicle was the "Seep," built to the design of the 1/4-ton Ford GPA. It was intended to ferry soldiers to and from ships off-shore. But they were too small, difficult to maneuver and in any significant waves, the Seep sank. The 1/4-ton Seep was shipped in small quantities to Europe and the islands of the South Pacific, working well in shallow waters and along narrow roads. It was not capable, however, of its assigned mission - ship to shore supply of cargo.

The National Defense Research Committee (NDRC) was headed by Palmer C. Putnam, who was in charge of a team with an impossible mission – design an amphibious vehicle large than the Seep that could move supplies directly from the ship to shore. The vehicle was required to perform as well on land as other vehicles of its size and type. It was to have sufficient sea-going capabilities: handle rough sea swells, high surf and have the ability to drive over reefs and sandbars.

The DUKW (pro-. nounced duck) was conceived by Rod Stevens, boat designer, and Dick Kerr, transportation specialist for Arabian-American Oil Company. PC Putman became the project chairman of the national Defense research Committee (NDRC), which became the Office of Strategic Research and Development (OSRD).

The DUKW was designed to discharge a platoon of men. Putnam’s ideal solution was to simply convert the standard truck – the GMC 353 series 2-1.2 ton. These GMCs were already in production, so design drawings were prepared in record times and four prototypes quickly built. In June 1942, tests were performed in the Chesapeake Bay and Atlantic Ocean and off-road tests at Fort Belvoir, VA and loading capability tests at Fort Eustis.

Scientists planned DUKW [D (model year), U (amphibian), K (all-wheel drive), W (dual rear axle)] as an Army truck that could also cross rivers and carry men and material ashore across beaches. Initially the Army wanted no part of this silly civilian truck. Even after the completion of a prototype DUKW the Army took no interest until engineers used the prototype to save the lives of seven Coast Guardsmen grounded in a storm on the back shore of Cape Cod. Suddenly the Army was interested. By July 1942, a well-attended demonstration at Fort Story, VA ensured the final acceptance of the DUKW. The pattern was standardized in October 1942. An order was placed for 2,000 of the DUKW-353 series.

The US Navy, responsible for the operation of all boats and ships, simply did not have enough men to train and operate all the various landing craft rolling off assembly lines. In early 1942, the Navy requested that the Army train and man some landing craft and all of the DUKWs. Initially, this mission was assigned to the Corps of Engineers. The First Engineer Amphibian Command was established early in the summer of 1942.

Army training took place at an Aquatic Park near the San Francisco Port of Embarkation in California. There was not a training model to follow and little time. The Engineer Amphibian Command was required to recruit, procure equipment and develop a training program almost simultaneously. A Boat Training Center was established at Camp Edwards, MA. Local civilian boat and yacht companies taught boat maintenance courses. The initial course of instruction was 3 weeks, but the need for lengthening the course was evident. Even after two months of training, soldiers were still not prepared to operate this complex new vehicle under wartime conditions.

Instructors and maintenance officers were sent to General Motors Corporation's War Products School in the fall of 1943. Various civilian companies taught 1,065 instructors about marine diesel engines, harbor operations, and offloading procedures. Before a sufficient number of landing ships were in service, it was necessary to use booms to transport vessels for setting the DUKWs into the water. This procedure was lengthy and difficult.

The 2nd Brigade, 87th Engineer Battalion was trained and issued DUKWs and other equipment. At the request of General Douglas MacArthur, they embarked for the Pacific in mid-January 1943. The first training exercise for the DUKW came in March 1943 when the 2nd Brigade landed troops on Noumea, New Caledonia. The land was small and involved only a few DUKWs and other landing craft, but it was successful. The amphibian engineers and the DUKW had proven their merit.

Eventually, the number of DUKW companies grew and the Transportation Corps established 15 Amphibious Truck Battalions and Headquarters Detachments, in order to assemble DUKW companies all under one command. In just a few short months, the Army had come a long way in perfecting amphibious landing techniques and what was needed to put troops ashore.

The DUKW proved invaluable during the invasion of Salerno, Italy. Between 9 September and 1 October 1943, 90 landing craft and 150 DUKWs moved 190,000 troops, 30,000 vehicles and 12,000 tons of supplies across the invasion beaches to Salerno. Operation Blue Jay used DUKWs for beaching operations in Sicily.

A shortage of LCT's, needed to unload Liberty ships, developed at the beginning of February 1944. Most of these craft had been in service for more than a year without overhaul and they frequently broke down. On 6 February only fifteen were available, a number that was increased to twenty-two by 12 February. As a stop-gap, from ten to twenty LCI's were successfully employed in unloading supplies at the beachhead Anzio in Italy. An effort was made to persuade the Liberty ships to come in closer to shore so that they could be unloaded directly by DUKW's, but ship captains were reluctant to do so in the face of heavy shelling. Between 450 and 490 DUKW's were in use at Anzio. The craft situation greatly eased at the end of February 1944, when sufficient LCT's again became available.

In the fall of 1943, an area on the southwest coast of England at Slapton Sands was ordered evacuated of all civilians. About 3,000 people, livestock, equipment and personal belongings were to be totally evacuated by 20 December 1943. They were sworn to secrecy as to the reason for their movement. Slapton Sands covered about 30,000 acres. The area along the beach had similar characteristics of beach and tide as Utah Beach - the proposed invasion and landing area in Normandy, France. Slapton Sands was used for numerous training and assault exercises. It accustomed the assault troops to the kind of terrain they would be encountering, tested and prepared the equipment with waterproofing, and procedures in demolition of obstacles.

Landing craft were assigned from various bases along the south Devon coast, including several DUKW companies, to carry troops and equipment on a sea journey of the same length and time as it would take to cross the English Channel to Normandy, France. Soldiers practiced landing on the beach and loading and unloading supplies. These rehearsals for the most part were very successful, and lessons in coordination were learned, which were applied to the actual invasion.

Early lessons by the Engineer Special Brigades were integrated into DUKW use during the Normandy Invasion in 1944. Nineteen companies were allocated to the invasion: 12 assigned to Omaha Beach, and 7 to Utah Beach. All were loaded with ammunition and other cargo, which would be crucial during the early stages of the invasion. The DUKWs embarked on LSTs in Weymouth, England on 5 June 1944, and moved across the channel for the invasion. LSTs off-loaded DUKWs 14 miles offshore shortly before the attack began. The DUKWs formed two columns and headed for shore.

The 453rd, 458th and 459th Transportation Corps Amphibious Truck Companies were assigned to the initial assault. Their mission was to deliver their cargo, then shuttle between the beach and the ships, offloading supplies and establishing supply and ammunition dumps. From June 6-7, 1944, the three companies lost 41 DUKWs while delivering supplies from ships to supply dumps established just behind the front lines. The ability to move vital supplies directly to the front lines, and the courage of the crews under enemy fire made the DUKW a vital, integral part of the Normandy Invasion.

After D-Day, the DUKW became indispensable in unloading vessels. Until port facilities could be rebuilt, they were crucial for moving supplies. Between June 6 1944 and May 8 1945, DUKWs moved 5,050,000 tons of the 15,750,000 tons unloaded by the allies in Europe during the war, over the course of the 90 days when the enemy held all available ports.

The DUKWs were used for one last amphibious operation in Europe -- the famous Rhine River crossing in Germany, at the end of March 1945. During this operation, 370 DUKWs were used to move men and supplies. During the early hours of the morning of 26 March 1945, under cloudy skies and protected by clouds of artificial fog, troops of the US 7th Army under General Patch crossed the Rhine River in Germany.

While the DUKWs were busy in Europe, their numbers were increased and their duties expanded in the Pacific Theater. Thirteen full companies were in the invasion of the Philippines. At Tacloban (the capital city of Leyte) in April 1945, 20 DUKWs from the 813th Amphibian Truck Company moved 1,847 tons of supplies in a 24-hour period. This required a 9-1/2 mile round trip from the ships, to a supply dump, and back again with each vehicle averaging over 92-tons of cargo.

DUKWs were invaluable during the capture of Manila. Although the Japanese had filled the harbor with sunken wreckage, the Army captured the city and supplied the troops using the DUKW. In the final battle on Okinawa, the DUKW was indispensable in moving artillery pieces and ammunition directly to the troops fighting against the Shuri Line, near Naha. Supplying and developing the beachhead had, by Landing plus 3, made substantial progress. Supply ships were run in to the reef's edge, where they unloaded into trucks or DUKWs.

By the end of World War II, a total of 21,147 DUKWs had been built. The Army had organized 70 Amphibious Truck Companies and assigned over 12,829 soldiers to operate and maintain them.

After World War II, the United States, Britain, France and Australia kept a reduced number of DUKWs in service. When the conflict in Korea began, the U.S. reactivated and deployed DUKW units. The 1st Transportation Replacement Training Group at Fort Story, VA, provided necessary training for DUKW crewman, and insured that DUKW units at the front were adequately staffed. DUKWs were instrumental in getting cargo to shore at Pusan, Korea, and later at Inchon, Korea.

D = built in 1942
U = amphibious 2-1/2 ton truck
K = front wheel drive
W = rear wheel drive
Length: . . . . . . . . . . . . . 31 ft
Width: . . . . . . . . . . . . . .8 ft 2 in
Height: . . . . . . . . . . . . . .8 ft 10 in
Weight, net: . . . . . . . . . . 14,880 lbs
Payload: . . . . . . . . . . . . .5,175 lbs
Gross: . . . . . . . . . . . . . . 20,055 lbs
Armament: Provision for M36 truck mount
For antiaircraft machine guns
XM147 DUKW “Super Duck”

The XM147 DUKW “Super Duck” was an Army amphibious vehicle built in a two-year period and tested at Aberdeen Proving Ground from 1956 to 1957. The Super DUKW handled like a truck that could swim. The Army needed a vehicle that handled like a boat in the water and truck on land. In 1953 the prototype XM-147 superdukw with a 145 hp engine began testing. The Super DUKW was based upon the post WW2 M135/211 GMC automatic power train. It could carry 4 tons of cargo. with a speed of 50 miles on road and 7,5 miles on the water. It had an all metal cab with sliding side windows and 15.50 X 20 tires. The Super DUCW had problems with breaks, steering and engine cooling system. The shape under water made that the water speed did not match the engine power. Made by General Motors, it was in service from 1953 through 1980.

XM158 Drake
The XM158 Drake was an 8 ton 8 wheel truck with an aluminium hull and 2 husky engines. It was intended to be the successor to be for the Dukw, but only a handful of prototypes were built by GM, the first in 1956. It was 42 feet long and 10 feet wide. The right engine drove on hard suface the second and forth axle. On soft ground the left engine is also switched on and that drives the first and third axle. There were 12 forward gears and a torque converters on each engine. It did 45 mph on land and 7 knots in water. In the water each engine drove a propeller that ascended and decended by two air lift cylinders.

Below picture from National Archives

Photo below was submited by Fielding Tyler,
458th Vehicles Ft Story, VA 1946

Bill Northrop found these two photo's on the internet