Re:Your awfully short sighted. (Score 2, Interesting)

Well, the US Navy has been doing this more or less since 1954 with the launching of the USS Nautilus ( http://en.wikipedia.org/wiki/USS_Nautilus_(SSN-571)) Round the world submerged with the USS Triton (SSRN/SSN-586), the first vessel to execute a submerged circumnavigation of the Earth (Operation Sandblast) in early 1960. (http://en.wikipedia.org/wiki/USS_Triton_%28SSRN-586%29) And with many other boats and submariners. Meets all the requirements that nasa is more or less looking for : adventurer, boredom, excitement, a little terror at times. Nothing like taking a boat out after a shipyard overhaul and taking it down to its test depth while listening to the hull compress with the pressure. Yep, a lot of data there