A
conning tower is a raised platform on a ship or submarine, often armored, from which an officer can con the vessel;
i.e., give directions to the
helmsmanA helmsman is a person who steers a ship, sailboat, submarine, or other type of maritime vessel. On small vessels, particularly privately-owned noncommercial vessels, the functions of skipper and helmsman may be combined in one person. On larger vessels, there is a separate officer of the watch,...
. It is usually located as high on the ship as practical, to give the conning team good visibility.
The verb 'conn' probably stems from the verb "conduct" rather from another plausible precedent, the verb "control". It is noted that the conning tower allows for efficient reconnaissance.
Admiral Douglas Monaster, from HMS
Malefactor, is credited with using the term "control tower".
Surface ships
On surface ships, the conning tower was a feature of all
battleshipA battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...
s and
armored cruiserThe armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...
s from about 1860 to the early years of
World War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. Located at the front end of the
superstructureA superstructure is an upward extension of an existing structure above a baseline. This term is applied to various kinds of physical structures such as buildings, bridges, or ships...
, the conning tower was a heavily-armored cylinder, with tiny slit windows on three sides providing a reasonable
field of viewThe field of view is the extent of the observable world that is seen at any given moment....
. Designed to shield just enough personnel and devices for navigation during battles, its interior was cramped and basic, with little more than
engine order telegraphAn engine order telegraph or E.O.T., often also chadburn, is a communications device used on a ship for the pilot on the bridge to order engineers in the engine room to power the vessel at a certain desired speed...
s, 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 batteriesA floating battery is a kind of armed watercraft, often improvised or experimental, which carries a heavy armament but has few other qualities as a warship.An early appearance was during the Great Siege of Gibraltar....
at the
Battle of KinburnThe Battle of Kinburn/Kil-Bouroun was a naval engagement during the final stage of the Crimean War. It took place on the tip of the Kinburn Peninsula on 17 October 1855...
. They were then fitted to the first ironclad the
French battleship La GloireThe French Navy's La Gloire was the first ocean-going ironclad battleship in history.She was developed following the Crimean War, in response to new developments in naval gun technology, especially the Paixhans guns and rifled guns, which used explosive shells with increased destructive power...
. The first Royal Navy conning tower appeared on
HMS WarriorHMS Warrior was the first iron-hulled, armour-plated warship, built for the Royal Navy in response to the first ironclad warship, the French Gloire, launched a year earlier....
which had 3 inches of armour.
In the
Royal NavyThe Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
(RN), the conning tower became a massive structure reaching weights of hundreds of tons on the
Admiral class battlecruiserThe Admiral-class battlecruisers were a class of four British Royal Navy battlecruisers designed near the end of World War I. Their design began as a improved version of the s, but it was recast as a battlecruiser after Admiral John Jellicoe, commander of the Grand Fleet, pointed out that there was...
(such as
HoodHMS Hood was the last battlecruiser built for the Royal Navy. One of four s ordered in mid-1916, her design—although drastically revised after the Battle of Jutland and improved while she was under construction—still had serious limitations. For this reason she was the only ship of her class to be...
), and formed part of a massive armoured citadel (
superstructureA superstructure is an upward extension of an existing structure above a baseline. This term is applied to various kinds of physical structures such as buildings, bridges, or ships...
) on the mid-1920s
Nelson-classThe Nelson class was a class of two battleships of the British Royal Navy, built shortly after, and under the terms of, the Washington Naval Treaty of 1922...
battleships which had armour over a foot thick. The
King George V classThe King George V-class battleships were the most modern British battleships used during World War II. Five ships of this class were built and commissioned: King George V , Prince of Wales , Duke of York , Howe , and Anson .The Washington Naval Treaty of 1922 limiting all of the number,...
, 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.
The
United States NavyThe United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
had mixed opinions of the conning tower, pointing out that its weight, high above the ship's center of gravity, did not contribute directly to fighting ability. Beginning in the late 1930s, as
radarRadar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
surpassed visual sighting as the primary method of detecting other ships, battleships began reducing or eliminating the conning tower. The
battle of GuadalcanalThe Naval Battle of Guadalcanal, sometimes referred to as the Third and Fourth Battles of Savo Island, the Battle of the Solomons, The Battle of Friday the 13th, or, in Japanese sources, as the , took place from 12–15 November 1942, and was the decisive engagement in a series of naval battles...
during
World War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
briefly slowed this trend: when the
Japanese battleship Kirishimawas a warship of the Imperial Japanese Navy during World War I and World War II. Designed by British naval engineer George Thurston, she was the third launched of the four Kongō-class battlecruisers, among the most heavily armed ships in any navy when built...
hit
South Dakota (BB-57)USS South Dakota was a battleship in the United States Navy from 1942 until 1947. The lead ship of her class, South Dakota was the third ship of the US Navy to be named in honor of the 40th state. During World War II, she first served in a fifteen-month tour in the Pacific theater, where she saw...
on the superstructure, many exposed crewmen were killed or wounded yet Captain Gatch declined to use South Dakota's armoured conning tower during the battle. Even that demonstration, however, did not halt the trend, and soon the heavy battleship conning towers were removed from
USS PennsylvaniaUSS Pennsylvania was a United States Navy super-dreadnought battleship. She was the third Navy ship named for the state of Pennsylvania....
(BB-38),
Tennessee (BB-43)USS Tennessee , the lead ship of her class of battleship, was the third ship of the United States Navy named in honor of the 16th US state. During World War II in the Pacific Theater, she was damaged during the attack on Pearl Harbor in December 1941 but was repaired and modernized...
,
California (BB-44)USS California , a Tennessee-class battleship, was the fifth ship of the United States Navy named in honor of the 31st state. Beginning as the flagship of the Pacific Fleet, she served in the Pacific her entire career. She was sunk in the attack on Pearl Harbor at her moorings in Battleship Row,...
, and
West Virginia (BB-48)USS West Virginia , a , was the second ship of the United States Navy named in honor of the 35th state.Her keel was laid down on 12 April 1920 by the Newport News Shipbuilding and Drydock Company of Newport News, Virginia. She was launched on 17 November 1921 sponsored by Miss Alice Wright Mann,...
,
during their post-
Pearl HarborPearl Harbor, known to Hawaiians as Puuloa, is a lagoon harbor on the island of Oahu, Hawaii, west of Honolulu. Much of the harbor and surrounding lands is a United States Navy deep-water naval base. It is also the headquarters of the U.S. Pacific Fleet...
attack reconstructions and replaced with much lighter
cruiserA cruiser is a type of warship. The term has been in use for several hundreds of years, and has had different meanings throughout this period...
-style conning towers.
By the end of
World War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, US ships were designed with expanded weather bridges enclosing the armored conning towers. On
Iowa-class battleshipsThe Iowa-class battleships were a class of fast battleships ordered by the United States Navy in 1939 and 1940 to escort the Fast Carrier Task Forces which would operate in the Pacific Theater of World War II. Six were ordered during the course of World War II, but only four were completed in...
, the conning tower is a vertical armor-plated cylinder with slit windows located in the middle of the bridge, climbing from deck 3 all the way up to the
flying bridgeA flying bridge is a area on top of, or at the side of, a ship's pilothouse, or closed bridge, that serves as an operating station for the ship's officers in good weather or when maneuvering in port, where good views along the ship sides are important...
on the O5.
With the demise of battleships after World War II, along with the advent of missiles and nuclear weapons during the
Cold WarThe Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
, modern warships no longer feature conning towers.
Submarines
The conning tower of a
submarineA submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
was a small watertight compartment within its
sailIn naval parlance, the sail or fin of a submarine is the tower-like structure found on the dorsal surface of submarines...
(or fin in British usage) equipped with instruments and controls and from which the
periscopeA periscope is an instrument for observation from a concealed position. In its simplest form it consists of a tube with mirrors at each end set parallel to each other at a 45-degree angle....
s were used to direct the boat and launch
torpedoThe modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...
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-classThe Virginia class is a class of nuclear-powered fast attack submarines in service with the United States Navy. The submarines are designed for a broad spectrum of open-ocean and littoral missions...
—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.