The submarine has a transport apparatus (8) releasably and externally fixed on a cylindrical bottom structure (2) in a region below an upper deck (6) by using a form-fit closure unit. The form-fit closure unit is operatively connected with an actuator device, which is manually controllable from the upper deck. The transport apparatus is arranged in a region at a long side of the bottom structure. A structure (4) forming the upper deck is passed into the region at the long side of the bottom structure.
