I was thinking the same thing ... this image would work perfectly in the 'Negative Space' contest. I love being on or in water, so I woundn't mind this view of the submarine. Fantastic capture.
I can't believe I havn't noticed this before now, it's just my kind of thing. I love darkness and shadow used as a strength of a photo or painting and thats just what you've done. There are several layers working here with plenty of detail in each, fore, middle and distance. The repeating ovals of chain, port and glass make a nice subliminal pattern too. Well spotted and taken.