So, one of the things we do is study all those different sounds to help us out. Officer: Conn, sonar, new contact, Sierra 4-1. Alfa-class Soviet submarine. More from How Real Is It?

The US Navy spends a lot of time in the Arctic ice, but it's the way the service's boats bust through the icepack that most impressive. This post is appearing on Autoblog Military, Autoblog's sub ...