Submarines
The conning tower of a submarine was a small watertight compartment within its sail (or fin in British usage) equipped with instruments and controls and from which the periscopes were used to direct the boat and launch torpedo attacks. It should not be confused with the submarine's control room, which was directly below it in the main pressure hull; or the bridge, a small exposed platform in the top of the sail.
As improvements in technology allowed the periscopes to be made longer—then to be eliminated altogether, as in the Virginia-class—it became unnecessary to raise the conning station above the main pressure hull. The additional conning tower pressure hull was eliminated and its functions were added to the command and control center. Thus it is incorrect to refer to the sail of a modern submarine as a conning tower.
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