They were used by submarines to navigate when not in open waters, They were also used by submarines and anti-submarine ships to locate enemy submarines.
Because it's impossible to navigate properly without one.
This sounds like it's probably the sonar system of a submarine.
Very sophisticated inertial guidance systems. Combined with occasional satnav validations.
Naval submarines do not dive deep enough to go near underwater mountains. This is contrary to what you may have seen in the movies. They use sounding charts to determine the depth of the water in which they are navigating. They avoid such underwater objects. Research submarines use cameras and sonar, as well as charts, to guide them.
There are quite a few devices that have made sea exploration as you know it possible. Submarines are one of these devices.
1. Ballistic submarines 2. Attack submarines
Boats, Subs, Submarines, Home.
Submarines - poem - was created in 1917.
Dallas Submarines was created in 1920.
One of our Submarines was created in 1982.
Yes, North Korea has submarines