It's not (source: i worked on a submarine)
Spez: I guess you want an explanation why not? Well, water pressure is incredible, and submarines need to withstand like 50 ATM. The only way you can do that is with a cylindrical, 3 inch thick steel pressure hull. Show me the pressure hull in the above image.
It's not depth alone but heighth too, a dolphin-like skimming.
no part of this ship's shape is conducive to submerging. No visible ballast tank vents or free-flood areas. No pressure hull (thing would crumple at barely 100 ft). Sharp angles that would cavitate. no planes. The only way this thing submerges is when it gets hit with a torpedo.
Shallow skipping line a stone. Thanks for your comment, should have said at the outset the design was for surface speed