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Ocean-going tug

U.S. Maritime Commission type V4-M-A1

The Maritime Commission’s V4 tug, with a length of 194 feet, displacement of 1,613 tons, and capable of a speed of 14 knots (6 knots towing), were among the largest and most powerful tugs in the world when they were built. Two diesel engines powered the Kort nozzle propulsion system that provided the tugs with faster towing speeds.  A boom and winch provided 10 tons of lift capacity, and each tug also included a towing engine and gun platform.

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The V4 tugs mainly conducted long distance towing of concrete barges. Notably, a number of V4s participated in Operation Neptune, towing the concrete caissons from the United States to Great Britain and then again to  the coast of France, where the military used them to create the artificial harbors critical to the success of the Normandy Invasion in June 1944.

Throughout the course of the war, six shipyards completed 49 of these tugs, most of which were delivered in 1943.


Detailed view of the stern and cargo boom.


Overhead view of the model with a focus on the weather deck above the pilot house.


Head-on view of the model, with the focus on the bridge and forward gun.


Port view of the model, with a focus on the life boats and emergency life rafts.


(Maritime Administration Heritage Asset, Object 1971.007.0001)