A device for launching torpedos
, shown here is the tube used on submarines
Some crude ASCII art
to show the component parts;
/ ____________________________ \
Inner> | |_/ Torpedo \ | Outer
Door | | \____________________________/ | Door
(Breech) \_ ________________________________________________/ (muzzle)
The tube is drained, and the breech (inner door, at left in the diagram) opened. A torpedo
is inserted into the tube and the breech is shut. The tube is then flooded from the sea (via a connection not shown on the diagram), the outer (muzzle) door is then opened. Pressure is introduced behind the torpedo, which pushes the torpedo out of the tube. The outer door is then closed and the cycle can begin again.
Torpedo tubes on surface vessels are similiar, but don't require flooding or draining if they are located above the waterline.