Naval mine
A naval mine is a self-contained explosive weapon placed in water to damage or destroy surface ships or submarines. Similar to anti-personnel and other land mines, and unlike purpose launched naval depth charges, they are deposited and left to wait until, depending on their fuzing, they are triggered by the approach of or contact with any vessel.
Naval mines can be used offensively, to hamper enemy shipping movements or lock vessels into a harbour; or defensively, to create "safe" zones protecting friendly sea lanes, harbours, and naval assets. Mines allow the minelaying force commander to concentrate warships or defensive assets in mine-free areas giving the adversary three choices: undertake a resource-intensive and time-consuming minesweeping effort, accept the casualties of challenging the minefield, or use the unmined waters where the greatest concentration of enemy firepower will be encountered.
Although international law requires signatory nations to declare mined areas, precise locations remain secret, and non-complying parties might not disclose minelaying. While mines threaten only those who choose to traverse waters that may be mined, the possibility of activating a mine is a powerful disincentive to shipping. In the absence of effective measures to limit each mine's lifespan, the hazard to shipping can remain long after the war in which the mines were laid is over. Unless detonated by a parallel time fuze at the end of their useful life, naval mines need to be found and dismantled after the end of hostilities; an often prolonged, costly, and hazardous task.
Modern mines containing high explosives detonated by complex electronic fuze mechanisms are much more effective than early gunpowder mines requiring physical ignition. Mines may be placed by aircraft, ships, submarines, or individual swimmers and boatmen. Minesweeping is the practice of the removal of explosive naval mines, usually by a specially designed ship called a minesweeper using various measures to either capture or detonate the mines, but sometimes also with an aircraft made for that purpose. There are also mines that release a homing torpedo rather than explode themselves.
Description
Mines can be laid in many ways: by purpose-built minelayers, refitted ships, submarines, or aircraft—and even by dropping them into a harbour by hand. They can be inexpensive: some variants can cost as little as US $2,000, though more sophisticated mines can cost millions of dollars, be equipped with several kinds of sensors, and deliver a warhead by rocket or torpedo.Their flexibility and cost-effectiveness make mines attractive to the less powerful belligerent in asymmetric warfare. The cost of producing and laying a mine is usually between 0.5% and 10% of the cost of removing it, and it can take up to 200 times as long to clear a minefield as to lay it. Parts of some World War II naval minefields still exist because they are too extensive and expensive to clear. Some 1940s-era mines may remain dangerous for many years.
Mines have been employed as offensive or defensive weapons in rivers, lakes, estuaries, seas, and oceans, but they can also be used as tools of psychological warfare. Offensive mines are placed in enemy waters, outside harbours, and across important shipping routes to sink both merchant and military vessels. Defensive minefields safeguard key stretches of coast from enemy ships and submarines, forcing them into more easily defended areas, or keeping them away from sensitive ones.
Shipowners are reluctant to send their ships through known minefields. Port authorities may attempt to clear a mined area, but those without effective minesweeping equipment may cease using the area. Transit of a mined area will be attempted only when strategic interests outweigh potential losses. The decision-makers' perception of the minefield is a critical factor. Minefields designed for psychological effect are usually placed on trade routes to stop ships from reaching an enemy nation. They are often spread thinly, to create an impression of minefields existing across large areas. A single mine inserted strategically on a shipping route can stop maritime movements for days while the entire area is swept. A mine's capability to sink ships makes it a credible threat, but minefields work more on the mind than on ships.
International law, specifically the Eighth Hague Convention of 1907, requires nations to declare when they mine an area, to make it easier for civil shipping to avoid the mines. The warnings do not have to be specific; for example, during World War II, Britain declared simply that it had mined the English Channel, North Sea and French coast.
History
Early use
Naval mines were first invented by Chinese innovators of Imperial China and were described in thorough detail by the early Ming dynasty artillery officer Jiao Yu, in his 14th-century military treatise known as the Huolongjing. Chinese records tell of naval explosives in the 16th century, used to fight against Japanese pirates. This kind of naval mine was loaded in a wooden box, sealed with putty. General Qi Jiguang made several timed, drifting explosives, to harass Japanese pirate ships. The Tiangong Kaiwu treatise, written by Song Yingxing in 1637, describes naval mines with a ripcord pulled by hidden ambushers located on the nearby shore who rotated a steel wheel flint mechanism to produce sparks and ignite the fuze of the naval mine. Although this is the rotating steel wheel's first use in naval mines, Jiao Yu described their use for land mines in the 14th century.The first plan for a sea mine in the West was by Ralph Rabbards, who presented his design to Queen Elizabeth I of England in 1574. The Dutch inventor Cornelius Drebbel was employed in the Office of Ordnance by King Charles I of England to make weapons, including the failed "floating petard". Weapons of this type were apparently tried by the English at the Siege of La Rochelle in 1627.
American David Bushnell developed the first American naval mine, for use against the British in the American War of Independence. It was a watertight keg filled with gunpowder that was floated toward the enemy, detonated by a sparking mechanism if it struck a ship. It was used on the Delaware River as a drift mine, destroying a small boat near its intended target, a British warship.
The 19th century
The 1804 Raid on Boulogne made extensive use of explosive devices designed by inventor Robert Fulton. The 'torpedo-catamaran' was a coffer-like device balanced on two wooden floats and steered by a man with a paddle. Weighted with lead so as to ride low in the water, the operator was further disguised by wearing dark clothes and a black cap. His task was to approach the French ship, hook the torpedo to the anchor cable and, having activated the device by removing a pin, remove the paddles and escape before the torpedo detonated. Also to be deployed were large numbers of casks filled with gunpowder, ballast and combustible balls. They would float in on the tide and on washing up against an enemy's hull, explode. Also included in the force were several fireships, carrying 40 barrels of gunpowder and rigged to explode by a clockwork mechanism.In 1812, Russian engineer Pavel Shilling exploded an underwater mine using an electrical circuit. In 1842 Samuel Colt used an electric detonator to destroy a moving vessel to demonstrate an underwater mine of his own design to the United States Navy and President John Tyler. However, opposition from former president John Quincy Adams, scuttled the project as "not fair and honest warfare". In 1854, during the unsuccessful attempt of the Anglo-French fleet to seize the Kronstadt fortress, British steamships , and HMS Firefly suffered damage due to the underwater explosions of Russian naval mines. Russian naval specialists set more than 1,500 naval mines, or infernal machines, designed by Moritz von Jacobi and by Immanuel Nobel, in the Gulf of Finland during the Crimean War of 1853–1856. The mining of Vulcan led to the world's first minesweeping operation. During the next 72 hours, 33 mines were swept.
The Jacobi mine was designed by German-born, Russian engineer Jacobi, in 1853. The mine was tied to the sea bottom by an anchor. A cable connected it to a galvanic cell which powered it from the shore, the power of its explosive charge was equal to of black powder. In the summer of 1853, the production of the mine was approved by the Committee for Mines of the Ministry of War of the Russian Empire. In 1854, 60 Jacobi mines were laid in the vicinity of the Forts Pavel and Alexander, to deter the British Baltic Fleet from attacking them. It gradually phased out its direct competitor the Nobel mine on the insistence of Admiral Fyodor Litke. The Nobel mines were bought from Swedish industrialist Immanuel Nobel who had entered into collusion with the Russian head of navy Alexander Sergeyevich Menshikov. Despite their high cost the Nobel mines proved to be faulty, exploding while being laid, failing to explode or detaching from their wires, and drifting uncontrollably, at least 70 of them were subsequently disarmed by the British. In 1855, 301 more Jacobi mines were laid around Krostadt and Lisy Nos. British ships did not dare to approach them.
In the 19th century, mines were called torpedoes, a name probably conferred by Robert Fulton after the torpedo fish, which gives powerful electric shocks. A spar torpedo was a mine attached to a long pole and detonated when the ship carrying it rammed another one and withdrew a safe distance. The submarine used one to sink on 17 February 1864. A Harvey torpedo was a type of floating mine towed alongside a ship and was briefly in service in the Royal Navy in the 1870s. Other "torpedoes" were attached to ships or propelled themselves. One such weapon called the Whitehead torpedo after its inventor, caused the word "torpedo" to apply to self-propelled underwater missiles as well as to static devices. These mobile devices were also known as "fish torpedoes".
The American Civil War of 1861–1865 also saw the successful use of mines. The first ship sunk by a mine,, foundered in 1862 in the Yazoo River. Rear Admiral David Farragut's famous command during the Battle of Mobile Bay in 1864, "Damn the torpedoes, full speed ahead!" refers to a minefield laid at Mobile, Alabama.
After 1865 the United States adopted the mine as its primary weapon for coastal defense. In the decade following 1868, Major Henry Larcom Abbot carried out a lengthy set of experiments to design and test moored mines that could be exploded on contact or be detonated at will as enemy shipping passed near them. This initial development of mines in the United States took place under the purview of the US Army Corps of Engineers, which trained officers and men in their use at the Engineer School of Application at Willets Point, New York. In 1901 underwater minefields became the responsibility of the US Army's Artillery Corps, and in 1907 this was a founding responsibility of the United States Army Coast Artillery Corps.
The Imperial Russian Navy, a pioneer in mine warfare, successfully deployed mines against the Ottoman Navy during both the Crimean War and the Russo-Turkish War.
During the War of the Pacific, the Peruvian Navy, at a time when the Chilean squadron was blockading the Peruvian ports, formed a brigade of torpedo boats under the command of the frigate captain Leopoldo Sánchez Calderón and the Peruvian engineer Manuel Cuadros, who perfected the naval torpedo or mine system to be electrically activated when the cargo weight was lifted. This system was employed on 3 July 1880, in front of the port of Callao, when the gunned transport Loa was sunk while capturing a sloop mined by the Peruvians. A similar fate occurred to the gunboat schooner Covadonga in front of the port of Chancay, on 13 September 1880 when a captured pleasure boat exploded while being hoisted on its side.
During the Battle of Tamsui, in the Keelung Campaign of the Sino-French War, Chinese forces in Taiwan under Liu Mingchuan took measures to reinforce Tamsui against the French; they planted nine torpedo mines in the river and blocked the entrance.