Japanese minisub sunk during the attack on Pearl Harbor.
A minisubmarine is a submarine of less than 150 tons of weight, operated regularly by one or two people and with a crew of no more than 6 or 8, without accommodation on board. Normally this type of submarines work with a nurse boat, from where they are launched and recovered, besides providing lodging for the crew and the equipment of support.
There are civil and military mini-submarines, both types built and in operation. Those of the military type, work with surface vessels and submarines, as support ships. Non-combative civilian or military types are generally known as submersibles, and usually work with surface vessels.
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