That Submarine looks like the kind that you drop a little tablet in....it sinks to the bottom....fizzes and pops back up. Heh Heh Heh.....bring it fools....
I think that little tank behind the conning tower is where they add the baking soda...
I bet that a good look inside would reveal a couple of "exercise bikes" hooked up to the prop shaft for propulsion.
"Hashim! Yamir! Pedal harder! The Americans are escaping! Mohammed! Load more baking soda and prepare for Crash Dive!"