Shipyard President Charles C. West contacted the
Bureau of Construction and Repair in 1939 to propose building
destroyers at Manitowoc and transporting them through the
Chicago River,
Chicago Sanitary and Ship Canal,
Illinois River, and
Mississippi River in a floating
drydock towed by the
tugboat Minnesota. After evaluating the plan and surveying the shipyard, the Navy suggested building submarines instead. A contract for ten submarines was awarded on 9 September 1940. The Navy paid for lift machinery on Chicago's Western Avenue railroad bridge to clear a submarine. The 15-foot-draft submarines entered a floating drydock on the Illinois River to get through the 9-foot-deep Chain of Rocks Channel near the confluence of the Mississippi and
Missouri Rivers. Submarines left the drydock at New Orleans and reinstalled
periscope shears, periscopes, and
radar masts which had been removed to clear bridges over the river. Manitowoc had never built a submarine before, but the first was completed 228 days before the contract delivery date. Contracts were awarded for additional submarines, and the last submarine was completed by the date scheduled for the 10th submarine of the original contract. Total production of 28 submarines was completed for $5,190,681 less than the contract price. SS-361 through SS-364 were initially ordered as
Balao-class, and were assigned hull numbers that fall in the middle of the range of numbers for the
Balao class (SS-285 through SS-416 & SS-425–426). Thus, in some references they are listed with that class. However, they were completed by Manitowoc as
Gatos, due to an unavoidable delay in
Electric Boat's development of
Balao-class drawings. Manitowoc was a follow yard to Electric Boat, and was dependent on them for designs and drawings. == List of fleet submarines built by Manitowoc ==