Sonar was used widely in World War II in an effort to locate enemy submarines. It wasn't as sophisticated as it is today, but it did help. Actual numbers are difficult to come by, but sonar was effective in the successful attacks on several submarines.
Sonar
yes
sonar
Sonar was used to detect and hunt submarines in WW2
It's called Sonar.
Sonar, RADAR and satellites and space travel improved the accuracy of maps after World War 2.
it looks a dome
Sonar helped map the ocean floor
In the Control Room; Sonar was very basic then, utilizing only a 2-head hydrophone array, and a very basic display.
Sonar with the Americans having the advantage.
Sonar
Rockets Jets Radar Sonar Atomic bomb Penicillin