Question: When you design a submarine, what are the general design features that are most important? Would streamlining be one?

Ryan Ladd answered on 18 Jun 2011:

Stream lining is definitely very important but that’s limited by the payload the submarine needs to carry. The payload is whatever is inside the submarine, sonar equipment, batteries, motors, various mechanical bits and, in manned submarines, people too!

Other things that are important is considering how you’re going to steer the submarine, this a lot more complex than on land as you need to move up and down as well.