This is an old and a common term. The torpedo has been used since the first submarine's were used in war time.
The weapon described is a depth charge.
They are called submarines
An underwater bomb is called a 'depth charge.
Torpedo...
Submarines todaee are used for underwater exploration,funn,new life underwater.
Submarines?
Submarines have sonars.
Ironclads are not the same thing as submarines. Ironclads do not go underwater completely even though the majority of their body may be underwater.
Yes the german submarines bombed the S.S Hato
To detect underwater mines and submarines.
Straight to the bottom of the ocean.
Sonar