It's always been tough to make submarines go all that fast due to the drag they get when trying to plow through water. It's a lot heavier than air, don't cha know! But the smarties at the Pentagon might have figured out a way around that little problem.
Their new speedster sub, dubbed the Underwater Express, can go 127 miles per hour as opposed to the standard sub's top speed of about 29 mph. How does it do it, pray tell? Well, it separates itself from the water by encasing itself in a giant gas bubble. The bubble can move through the water quickly, with no drag on the sub itself. Technically, the process is known as super-cavitation. Sounds pretty cool to us. We're looking forward for such tech to get implemented not just in real subs, but in The Hunt for Red October II.