Unique vessels do the heavy lifting for the U.S. Navy.

The U.S. Navy uses three specialized crane ships to help with heavy lifting.

Auxiliary Vessels
The U.S. Navy uses three Gopher-state class crane ships to help it lift, load and transport heavy equipment around the world. The crane ships are considered "Auxillary Vessels" by the U.S. Navy and crewed by civilians. The lead ship in the class is named after the northern state of Minnesota. The crane ships are equipped with large cranes to help lift and load a variety of heavy equipment ranging from Armored
Personnel Carriers (APCs) and tanks to construction equipment.
The crane ships used by the U.S. military entered service in 1986. All three vessels have been adapted from former Sea Witch-class container ships at the Bath Iron Works shipyard located in Bath, Maine. Each ship is outfitted with a crane, is nearly 700 feet long and can travel at a top speed of about 20 miles per hour. The ships are capable of carrying over 13,000 tons of equipment. They normally have a crew of 30 civilians when fully operational, and about 10 crewmen when docked or in reduced operating status