Conning tower

A conning tower is a raised platform on a ship or submarine, often armored, from which an officer can conn the vessel, i.e., give directions to the helmsman. It is usually located as high on the ship as practical, to give the conning team good visibility of the entirety of the ship itself and of ocean conditions and other vessels.

The verb “conn” probably stems from the verb “conduct” rather than from another plausible precedent, the verb “control”.

On surface ships, the conning tower was a feature of all battleships and armored cruisers from about 1860 to the early years of World War II. Located at the front end of the superstructure, the conning tower was a heavily armored cylinder, with tiny slit windows on three sides providing a reasonable field of view. Designed to shield just enough personnel and devices for navigation during battles, its interior was cramped and basic, with little more than engine order telegraphs, speaking tubes or telephones, and perhaps a steering wheel. At all other times than during battles, the ship would be navigated from the bridge instead. Conning towers were used by the French on their floating batteries at the Battle of Kinburn. They were then fitted to the first ironclad the French battleship La Gloire. The first Royal Navy conning tower appeared on HMS Warrior which had 3 inches of armour.

In the Royal Navy (RN), the conning tower became a massive structure reaching weights of hundreds of tons on the Admiral-class battlecruisers (such as HMS Hood), and formed part of a massive armoured citadel (superstructure) on the mid-1920s Nelson-class battleships which had armour over a foot thick. The King George V class, in contrast to the Nelson class had comparatively light conning tower protection with 4.5 inches sides, 3 inch front and rear, and 2 inch roof and deck. The RN's analysis of World War I combat revealed that command personnel were unlikely to utilize an armoured conning tower, preferring the superior visibility of unarmoured bridge positions. Older RN battleships that were reconstructed with new superstructures, had their heavily armoured conning towers removed and replaced with much lighter structures. These new conning towers were also placed much higher in the ship, for superior visibility. There is no evidence that RN captains and admirals utilized the armoured conning towers on those ships that did have them during World War II and Captain Kerr and Admiral Holland fought the Hood, for example, from her unarmoured bridge. Even in the USN, battleship captains and admirals preferred to use the unarmoured bridge positions during combat.

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