Very interesting video on how the USS Pennsylvania works, it is a nuclear powered submarine
that is powered by a lump of uranium the size of a fist

that provides all of the power to navigate and provide power for all of the daily operations and has been running since 1989 without having to refuel. Ever wonder how they get fresh air under water to last for months? How they launch a nuclear warhead? how they can make the submarine quiet to
avoid detection? See the answers in this video.

(Click On Below ) >>>
http://www.chonday.com/Videos/pen1usnav1