Here is the minisommergible Sassaroli, a concept that was never completed, of the Regia Marina. As is suggested by its name, the Sassaroli was a small submarine intended to carry one pilot and a single torpedo (attached under the submarine) for night attacks. Powered by an Alfa Romeo 200-horsepower 1001-B petrol engine, this submarine was expected to reach a speed of 28-30 nautical miles, with a maximum operating depth of 30 metres. With such a small footprint, this vessel did not have a battery to supply power to motors during a dive, as is common with many submarines. Instead, it provided the engine with an oxygen mix on its intake manifold. The driver of the vessel would have worn a respirator at all times to counter the threat of carbon dioxide buildup.

Built by myself, this minisommergible was photographed by xYoshii_. A fun project to build, I hope you enjoy it.