page_title: Conning tower
section_title: Surface ships
hierarchical_section_title: Conning tower / Surface ships
caption_attribution_description: English: Identifier: historyofmanufac00amer (find matches) Title: History of the manufacture of armor plate for the United States navy Year: 1899 (1890s) Authors: American Iron and Steel Association, comp Subjects: United States. Navy Armor-plate Publisher: Philadelphia, American Iron and Steel Association Contributing Library: The Library of Congress Digitizing Sponsor: The Library of Congress View Book Page: Book Viewer About This Book: Catalog Entry View All Images: All Images From Book Click here to view book online to see this illustration in context in a browseable online version of this book. Text Appearing Before Image: mitting the item of profit, would then read as follows: Cost of labor and material in double-forged, Harveyized, nick-el-steel armor, per ton $196.00 Allowance for maintenance at 10 per cent, on plant costing $3,-000,000 would be $300,000 per annum, which, on an outputof 2,000 tons per annum, would amount to, per ton 150.00 Add for nickel, to be fornished hereafter by the contractor, per ton 20.00 Making $366.00 Armor sold at $400 per ton would thus yield a profit of$34 per ton, amounting, on 2,000 tons per year, to $68,000,or 1.7 per cent, on the capital invested, nothing being al-lowed for interest on the capital. Senator Chandler hasdissented from the allowance of 10 per cent, for mainte-nance made by Secretary Herbert, and has estimated that6 per cent, would be sufl&amp;cient. This would reduce themaintenance charge per toh to $90, making the total cost C re g 3 5^2.9&#160;! St!?;?^^ ° re «&#160;~-cr*-o nO z O&#160;?0 s ^ p EX 7* m g V- re p-J ha^. re F re B*^ C ■• re re H ^ re &gt; z &gt; Text Appearing After Image: ARMOR PLATE FOR THE NAVY. \) / $306 per ton of armor, or a profit of $94 per ton, which,on an annual output of 2,000 tons, would be&#160;;188,000,or 4.7 per cent, on the investment.) CONGRESSIONAL LIMITATION OF PRICE. With these estimates before it Congress, on March 3,1897, established an arbitrary price of $300 per ton tobe paid for armor. To show approximately what thisprice means let it be assumed that for three years therehave been manufactured 2,000 tons of armor per year,which is about the average quantity, and which, at theprice of $300 per ton, would yield the gross sum of $1,-800,000, or $600,000 per year. The cost of the plant,with a fair allowance for working capital, would amountto about $4,000,000. If, therefore, armor should cost noth-ing to make, the above gross receipts per year would beonly 15 per cent, on the capital invested in a plant whichmay within a few years be worthless. Foreign govern-ments are satisfied to pay for the same quality of armorover $500 per ton. Amer Note About Images Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.
context_page_description: A conning tower is a raised platform on a ship or submarine, often armored, from which an officer in charge can conn the vessel, controlling movements of the ship by giving orders to those responsible for the ship's engine, rudder, lines, and ground tackle. It is usually located as high on the ship as practical, to give the conning team good visibility of the entirety of the ship, ocean conditions, and other vessels.
  The verb "conn" probably stems from the verb "conduct" rather than another plausible precedent, the verb "control".
context_section_description: 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.
  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 (RN) conning tower appeared on HMS Warrior which had 3 inches of armour.
  In the Royal Navy, 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-inch (110 mm) sides, 3-inch (76 mm) front and rear, and 2-inch (51 mm) roof and deck. The RN's analysis of World War I combat revealed that command personnel were unlikely to use 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 used the armoured conning towers on those ships that did have them during World War II, with, for example, Vice-Admiral Holland and Captain Kerr commanding Hood during the Battle of the Denmark Strait from her unarmoured bridge. Even in the United States Navy (USN), battleship captains and admirals preferred to use the unarmoured bridge positions during combat.
  The USN 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 radar surpassed visual sighting as the primary method of detecting other ships, battleships began reducing or eliminating the conning tower. The battle of Guadalcanal during World War II briefly slowed this trend: when the Japanese battleship Kirishima hit USS South Dakota on the superstructure, many exposed crewmen were killed or wounded yet Admiral Lee and Captain Davis of USS Washington declined to use the armoured conning tower during the battle. Soon the heavy battleship conning towers were removed from USS Pennsylvania, USS Tennessee, USS California, and USS West Virginia during their post-Pearl Harbor attack reconstructions and replaced with much lighter cruiser-style conning towers.
  By the end of World War II, US ships were designed with expanded weather bridges enclosing the armored conning towers. On Iowa-class battleships, the conning tower is a  17.3-inch (439 mm) thick vertical armor-plated cylinder with slit windows located in the middle of the bridge, climbing from deck 03 all the way up to the flying bridge on 05.
  With the demise of battleships after World War II, along with the advent of missiles and nuclear weapons during the Cold War, modern warships no longer feature conning towers.
caption: Armoured cylinder of USS Massachusetts's conning tower during construction
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