A naval mine is a self-contained explosive device placed in water to destroy ships or submarines. An explosive material is a material that either is chemically or otherwise Energetically unstable or produces a sudden expansion of the material usually accompanied A ship /ʃɪp/ is a large vessel that floats on water Ships are generally distinguished from Boats based on size A submarine is a Watercraft that can operate independently below water as distinct from a Submersible that has only limited underwater capability Unlike depth charges, they are deposited and left to wait until they are triggered by the approach of or contact with an enemy ship. Depth Charge is a character in the Beast Wars: Transformers universe Naval mines can be used offensively, to hamper enemy ships or lock them into a harbour; or defensively, to protect friendly ships and create "safe" zones. A harbor or harbour (see spelling differences) or haven, is a place where ships may shelter from the Weather or are stored

Mines can be laid in many ways: by purpose-built minelayers, refitted ships, submarines, or airplanes—and even by dropping them into a harbour by hand. Minelaying is the act of deploying explosive mines Historically this has been carried out by ships submarines and aircraft Overview Fixed-wing aircraft range from small training and recreational aircraft to Wide-body aircraft and military cargo aircraft. A harbor or harbour (see spelling differences) or haven, is a place where ships may shelter from the Weather or are stored They can be inexpensive: some variants can cost around a thousand United States dollars (USD) or so, although more sophisticated mines can cost millions of USD, be equipped with several kinds of sensors, and deliver a warhead by rocket or torpedo. The United States dollar ( sign: $; code: USD) is the unit of Currency of the United States; it has also been Typically a warhead is the Explosive material and Detonator that is delivered by a Missile, Rocket, or Torpedo. A rocket or rocket vehicle is a Missile, Aircraft or other Vehicle which obtains Thrust by the reaction of the The modern torpedo (historically called an automotive automobile locomotive or fish torpedo is a self-propelled explosive Projectile weapon launched above or below

Their flexibility and cost-effectiveness make mines attractive weapons in asymmetric warfare. Asymmetric warfare originally referred to War between two or more belligerents whose relative military power differs significantly The cost of producing and laying a mine is usually anywhere from 0. 5% to 10% of the cost to remove 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 minefields still exist, because they are too spread out and expensive to clear—and theoretically, some of these mines might stay active for hundreds of years.

There are three main uses of mines: offensive, defensive and psychological. The US Department of Defense defines psychological warfare ( PSYWAR) as" The planned use of Propaganda and other Psychological actions Offensive mines are placed in enemy waters, outside harbours and in important shipping routes to sink civilian and military ships. Defensive minefields protect a coast from enemy ships and submarines and force them into areas that are easier to defend. Minefields designed for psychological effect are usually placed in trade routes and are used to stop shipping to an enemy nation. A trade route is a logistical network identified as a series of pathways and stoppages used for the commercial transport of cargo They are also spread out thinly, to create a feeling of random minefields in large areas. A single mine along a shipping route can stop shipping for days until the entire area is swept.

International law requires nations to declare when they mine an area, in order to make it easier for civil shipping to avoid the mines. International law is the term commonly used for referring to the system of implicit and explicit agreements that bind together nation-states in adherence to recognized values and standards The warnings do not have to be specific; during World War II, Britain declared simply that it had mined the English Channel, North Sea, and French coast. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including The North Sea is a marginal, Epeiric sea of the Atlantic Ocean on the European Continental shelf. That did not stop Operation Sealion, Germany's planned invasion of Britain; Germany cancelled it for other reasons. Operation Sealion (Unternehmen Seelöwe was Germany's plan to invade the United Kingdom during World War II, beginning in 1940

Contents 1 History 2 Types 2.1 Contact mines 2.1.1 Limpet mines 2.1.2 Floating contact mines 2.1.2.1 Drifting contact mines 2.1.3 Bottom contact mines 2.1.4 Remotely controlled mines 2.1.5 Moored mines 2.1.6 Bottom mines 2.2 Influence mines 3 Unusual mines 4 Mine laying 4.1 Aerial mining in World War II 4.1.1 Germany 4.1.2 Soviet Union 4.1.3 United Kingdom 4.1.4 United States 4.1.5 Clearing WWII aerial mines 5 Damage 6 Countermeasures 6.1 Passive countermeasures 6.2 Active countermeasures 6.2.1 Mine sweeping 6.2.2 Mine hunting 6.2.3 Mine breaking 7 National arsenals 7.1 US Mines 7.2 Royal Navy 8 See also 9 References 9.1 Sources 10 Further reading 11 External links

History

The precursor to naval mines was first described by the early Ming Dynasty Chinese artillery officer Jiao Yu, in his 14th century military treatise known as the Huolongjing. The Ming Dynasty ( or Empire of the Great Ming ( was the ruling dynasty of China from 1368 to 1644 following the collapse of the Mongol -led Artillery (from French artillerie) is a military Combat Arm which employs any apparātus machine Jiao Yu ( Traditional and Simplified Chinese: 焦玉 Wade-Giles: Chiao Yü, Hanyu Pinyin: Jiāo Yù) was a Chinese The Huolongjing ( Wade-Giles: Huo Lung Ching; Traditional Chinese: 火龍經 rendered by its translator into English as ^[1] Chinese records tell of naval explosives in the 16^th century, used to fight against Japanese pirates (Wokou). This kind of naval mine was loaded in a wooden box, sealed by putty. Putty is a generic term for a plastic material similar in texture to Clay or Dough typically used in domestic construction and repair as a sealant or filler General Qi Jiguang made several timed explosive drifting explosives to harass Japanese pirate ships. Life Early life Qi Jiguang was born in the town of Luqiao (鲁橋 in Shandong province to a family with a long military tradition ^[2] However, in the Tiangong Kaiwu ('The Exploitation of the Works of Nature') treatise, written by Song Yingxing in 1637 AD, it describes naval mines with a rip cord pulled from a hidden ambusher located on the nearby shore, which would in turn rotate a steel wheellock flint mechanism to produce sparks and ignite the fuse of the naval mine. Song Yingxing ( Traditional Chinese:宋應星 Simplified Chinese:宋应星 Wade Giles: Sung Ying-Hsing; 1587-1666 AD was a Chinese Wheellock, wheel-lock or wheel lock, is a mechanism for firing a Firearm. ^[3] Although Song's writing represents the rotating steel wheellock's first use with naval mines, Jiao Yu had actually described their use for land mines back in the 14th century. A land mine is an Explosive device designed to be placed on or in the ground to explode when triggered by an operator or the Proximity of a vehicle person ^[4]

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. ^[3] The Dutch inventor Cornelius Drebbel was employed in the Office of Ordnance by King Charles I of England to make weapons, including a "floating petard" which proved a failure. Cornelius Jacobszoon Drebbel ( Alkmaar, Holland, 1572 - London, November 7 1633) was the Dutch Inventor Charles I, (19 November 1600 &ndash 30 January 1649 was King of England, Scotland and Ireland from 27 March 1625 until his execution. ^[5] Weapons of this type were apparently tried by the English at the Siege of La Rochelle in 1627. The Siege of La Rochelle was a result of a war between the French royal forces of Louis XIII of France and the Huguenots of La Rochelle in 1627-1628 ^[6]

However, an American, David Bushnell invented the first practical mine for use against the British in the American War of Independence. David Bushnell (1742 - 1824 of Saybrook Connecticut, was an American Inventor during the Revolutionary War. In this article the inhabitants of the thirteen colonies that supported the American Revolution are primarily referred to as "Americans" with occasional references to "Patriots" It was a watertight keg filled with gunpowder that was floated toward the enemy. Gunpowder is a an explosive mixture of Sulfur, Charcoal and Potassium nitrate (also known as saltpetre/saltpeter that burns rapidly producing volumes It was detonated by a percussion lock if it struck a ship.

In 1812 Russian engineer Pavel Shilling exploded an underwater mine using an electrical circuit. Baron Pavel L'vovitch Schilling, Paul Schilling (c1780 Reval (now Tallinn, Estonia) - 1836 St An electrical network is an interconnection of Electrical elements such as Resistors Inductors Capacitors Transmission lines Voltage In 1854, during the unsuccessful attempt of the Anglo-French fleet to seize Kronshtadt fortress, British steamships HMS Merlin, HMS Vulture and HMS Firefly were damaged by underwater explosions of Russian naval mines. Kronstadt (Кроншта́дт also spelled Kronshtadt, Cronstadt (Krone for Crown and Stadt for City) is a Russian Generally, more than 1500 naval mines, or infernal machines, designed by Moritz von Jacobi were set by Russian naval specialists in the Gulf of Finland during the Crimea War. Moritz Hermann (Boris Semyonovich von Jacobi (Борис Семёнович (Морис-Герман Якоби ( September 21, 1801 &ndash March 10 The Gulf of Finland ( Finnish: Suomenlahti, Russian: Финский залив, Finskiy zaliv, Swedish: Finska viken The Crimean War, also known in Russia as the Eastern War (Восточная война Vostochnaya Vojna) (March 1854–February 1856 was fought

The American Civil War saw the first successful Western use of mines by both sides. Causes of the war See also Origins of the American Civil War, Timeline of events leading to the American Civil War The coexistence of a slave-owning South The first ship sunk by a mine was the USS Cairo in 1862 in the Yazoo River. Service in the American Civil War Cairo was built in 1861 by James Eads and Co The Yazoo River is a River in the US state of Mississippi. The Yazoo River was named by French explorer La Salle in 1682 in reference to Rear Admiral David Farragut's famous statement, "Damn the torpedoes, full speed ahead!" refers to a minefield laid at Mobile, Alabama. Rear admiral is a Naval Commissioned officer rank above that of a Commodore and Captain, and below that of a Vice Admiral. David Glasgow Farragut ( July 5 1801 &ndash August 14 1870) was the first senior or "flag" officer of the United States Navy

In the 19^th century, mines were called torpedoes, a name likely conferred by Dennis Fletcher after the torpedo fish, which gives powerful electric shocks. The modern torpedo (historically called an automotive automobile locomotive or fish torpedo is a self-propelled explosive Projectile weapon launched above or below Electric rays (order Torpediniformes) are Fish that have a rounded body and a pair of organs capable of producing an Electric discharge, varying "Electrocute" redirects here For the band see Electrocute (band. A spar torpedo was a mine attached to a long pole and detonated when the ship carrying it rammed another one. A spar torpedo is a Weapon consisting of a Bomb placed at the end of a long pole or spar and attached to a Boat. The H. L. Hunley used one to sink the USS Housatonic on February 17, 1864. History Hunley and two earlier submarines were privately developed and paid for by Horace Lawson Hunley, James McClintock, and Baxter Watson Events 1500 - Battle of Hemmingstedt. 1600 - Philosopher Giordano Bruno is burned alive at Campo de' Fiori Year 1864 ( MDCCCLXIV) was a Leap year starting on Friday (link will display the full calendar of the Gregorian Calendar (or a Leap year 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. The Royal Navy of the United Kingdom is the oldest of the British armed services (and is therefore known as the Senior Service) Other "torpedoes" attached to ships or even launched under their own power. One such weapon, called the Whitehead Torpedo after its inventor, eventually drew the appellation from static devices to self-propelled underwater missiles. Robert Whitehead ( 3 January 1823 &ndash 14 November 1905) was an English engineer

The next major use of mines was in the Russo-Japanese War in 1904, sinking the Russian battleship Petropavlovsk, killing the fleet commander, Admiral Makaroff, and most of the crew. The Russo-Japanese War (日露戦争 Romaji: Nichi-Ro Sensō Русско-японская война Russko-Yaponskaya Voyna;, 10 February 1904 – 5 September Name New battleships in the Imperial Russian Navy got their names from famous land and naval battles of the 18th and 19th centuries. On the other side, two Japanese battleships were sunk by Russian mines in one day.

Many of early mines were fragile and dangerous to handle, with glass containers filled with nitroglycerin or mechanical devices that activated them upon tipping. Nitroglycerin ( NG) ( US spelling also known as nitroglycerine, ( UK Spelling trinitroglycerin, trinitroglycerine Several mine-laying ships were destroyed when their cargo exploded.

The U-boat fleet, which dominated much of the battle of the Atlantic, was small at the beginning of the war and much of the early action by German forces involved mining convoy routes and ports around Britain. U-boat is the anglicized version of the German word, itself an abbreviation of Unterseeboot ( undersea boat) and refers A convoy is a group of Vehicles (of any type but usually motor vehicles or ships traveling together for mutual support The German submarines also operated in the Mediterranean Sea and its coasts, in the Caribbean Sea, and along the U. For the region see Caribbean. The Caribbean Sea (kəˈrɪbiən or /ˌkærɨˈbiːən/ is a tropical Sea in the Western Hemisphere S. coast.

Initially contact mines were employed -- meaning that a ship had to physically strike one of the mines to detonate it -- usually tethered at the end of a cable just below the surface of the water. By the beginning of World War II most nations had also developed mines that could be dropped from aircraft, making it possible to lay them in enemy harbours (although they simply floated on the surface). The use of dredging and nets was effective against this type of mine, but this process was time consuming and involved closing harbors while it was completed.

Into this arena came a new mine threat. Most contact mines leave holes in ship's hulls, but some ships survived mine blasts, limping into port with buckled plates and broken backs. This appeared to be due to a new type of magnetic mine, detonating at a distance from the ship, and doing damage with the shockwave of the explosion. Often ships that had successfully run the gauntlet of the Atlantic crossing were destroyed entering freshly mineswept harbors on Britain's coast. More shipping was being lost than could be replaced, and Churchill ordered that the intact recovery of one of these new mines was of highest priority. Sir Winston Leonard Spencer-Churchill, KG, OM, CH, TD, FRS, PC, PC (Can ( 30 November 1874

The British experienced a stroke of luck in November 1939. A German mine was dropped from an aircraft onto the mud flats of the Thames estuary during low tide. The Thames Estuary is the area in which the River Thames meets the waters of the North Sea. As if this was not sufficiently good fortune, the land belonged to the army, and a base with men and workshops was at hand. Experts were dispatched from London to investigate the mine. They had some idea that the mines used magnetic sensors, so everyone removed all metal, including their buttons, and made tools out of non-magnetic brass. They disarmed the mine and rushed it to labs at Portsmouth, where scientists discovered a new type of arming mechanism. History See also History of Portsmouth There have been settlements in the area since before Roman times mostly being offshoots of Portchester, which

The mechanism had a sensitivity level that could be set, and the units of the scale were in milligauss. Gauss is a measurement for the strength of a magnetic field, demonstrating how it went off before coming into contact with the ship. In Physics, a magnetic field is a Vector field that permeates space and which can exert a magnetic force on moving Electric charges Using the detector from the mine, they were able to study the effect of a ship passing near it. A ship or large ferrous object passing through the earth's magnetic field will concentrate the field at that point. The mine's detector was designed to go off at the mid-point of the ship passing overhead.

From this data, methods were developed to clear the mines. Early methods included the use of large electromagnets dragged behind ships, or on low-flying aircraft (a number of older bombers like the Vickers Wellington were used for this). WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Both of these methods had the disadvantage of "sweeping" only a small strip. A better solution was found in the "Double-L Sweep" ^[7] using electrical cables dragged behind ships that passed large pulses of current through the seawater. This induced a large magnetic field and swept the entire area between the two ships. The older methods continued to be used in smaller areas. The Suez Canal continued to be swept by aircraft, for instance. The Suez Canal is a Canal in Egypt. Opened in 1869 it allows Water transportation between Europe and Asia without circumnavigation

While these methods were useful for clearing mines from local ports, they were of little or no use for enemy-controlled areas. These were typically visited by warships, and the majority of the fleet then underwent a massive degaussing process, where their hulls had a slight "south" bias induced into them. This offset the concentration effect almost to zero.

Initially major warships and large troopships had a copper degaussing coil fitted around the perimeter of the hull, energised by the ship's electrical system whenever in suspected magnetic-mined waters. Some of the first to be so-fitted being the carrier HMS Ark Royal and the liners RMS Queen Mary and RMS Queen Elizabeth which were used as troopships. An aircraft carrier is a Warship designed with Design In 1923 the Admiralty prepared plans for a ten year building programme which included a new aircraft carrier and 300 aircraft for the Fleet Air Arm Naming and construction With Germany launching their and into service the British did not want to be left out in this ship building race Maiden voyage At the start of World War II the Queen Elizabeth had been launched and was still in the process of fitting out This was felt to be impracticable for the myriad of smaller warships and merchant vessels, not least due to the amount of copper that would be required. It was found that 'wiping' a current-carrying cable up and down a ship' hull ^[8] temporarily cancelled the ships' magnetic signature sufficiently to nullify the threat. This started in late 1939, and by 1940 merchant vessels and the smaller British warships were largely immune for the few months at a time until they once again built up a field. Many of the boats that sailed to Dunkirk were degaussed in a marathon four day effort by degaussing stations. The Battle of Dunkirk was the defense and evacuation of the British and Allied forces that had been separated from the main body of the French defenses by the German advance

The Germans had also developed a pressure-activated mine and planned to deploy it as well, but they saved it for later use when it became clear the British had defeated the magnetic system.

Since World War II, mines have damaged or sunk 14 US Navy ships, whereas air and missile attacks have damaged four. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including

During the Korean War, mines laid by North Korean forces damaged 11 U. The Korean War refers to a period of military conflict between North Korean and South Korean regimes with major hostilities lasting from June 25 1950 until the S. naval vessels.

During the Iran-Iraq War from 1980 to 1988, the belligerents mined several areas of the Persian Gulf and nearby waters. The Persian Gulf, in the Southwest Asian region is an extension of the On April 14, 1988, the USS Samuel B. Roberts (FFG-58) struck an Iranian M-08/39 mine in the central Gulf shipping lane, wounding 10 sailors. Events 43 BC - Battle of Forum Gallorum: Mark Antony, besieging Julius Caesar 's assassin Decimus Junius Brutus in Year 1988 ( MCMLXXXVIII) was a Leap year starting on Friday (link displays 1988 Gregorian calendar) Commissioning and namesake The frigate was named for Samuel B A sea lane is regularly used Route for Ocean -going vessels. In the time of sailing ships they were not only determined by the distribution of land masses

During the Gulf War, Iraqi naval mines severely damaged USS Princeton (CG-59) and USS Tripoli (LPH-10). For a topic outline on this subject see List of basic Iraq topics. Mine Attack On the morning of 18 February 1991 during Operation Desert Storm, Princeton was patrolling an operating area 28 nautical miles off Failaka Vietnam Service 1967-1973 She served on three deployments to Vietnamese waters during the Vietnam War, participating in numerous operations

Types

Naval mines may be classified into two major groups.

Contact mines

The earliest mines were usually of this type. They are still used today, as they are extremely low cost compared to any other anti-ship weapon and are effective, both as a terror weapon and to sink enemy ships. Contact mines need to be very close to the target before they detonate, limiting the damage. (Read the section on damage, below, for explanation).

Early mines had mechanical mechanisms to detonate them, but these were superseded in the 1870s by the Hertz Horn (or chemical horn), which was found to work reliably even after the mine had been in the sea for several years. The mine's upper half is studded with hollow lead protuberances, each containing a glass vial filled with sulfuric acid. Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. When a ship's hull crushes the metal horn, it cracks the vial inside it, allowing the acid to run down a tube and into a lead-acid battery which until then contains no acid electrolyte. In electronics a battery is a combination of two or more Electrochemical cells which store chemical Energy which can be converted into electrical energy This energizes the battery, which detonates the explosive.

Earlier forms of the detonator used a vial filled with sulfuric acid, surrounded by the mixture of potassium perchlorate and sugar. Potassium perchlorate, a Perchlorate salt with the chemical formula K[[chlorine Cl]] O4, is a strong oxidizer. Sugar is a class of edible Crystalline substances mainly Sucrose, Lactose, and Fructose. When the vial was crushed, the acid ignited the perchlorate-sugar mix, and the resulting flame ignited the gunpowder charge.

During World War I the British heavily mined the English Channel and later large areas of the North Sea to prevent German submarines from using it. World War I (abbreviated WWI; also known as the First World War, the Great War, and the War to End All The North Sea is a marginal, Epeiric sea of the Atlantic Ocean on the European Continental shelf. A submarine is a Watercraft that can operate independently below water as distinct from a Submersible that has only limited underwater capability As the submarine could be at any depth down to the seabed, an American invention, the antenna mine, was widely used. The United States of America —commonly referred to as the This had a copper wire attached to a buoy that floated above the mine. The top part of the cable connecting the buoy to the weight on the seabed was also made of copper. The copper wire was insulated from the steel cable below it. If a submarine's steel hull touched the copper wire, the slight voltage produced because of the contact between two dissimilar metals was amplified and detonated the explosive.

Limpet mines

Limpet mines are a special form of contact mine which are attached to the target by magnets and left, and are so named because of the superficial similarity to the mollusk, limpet. Molluscs are animals belonging to the phylum Mollusca. There are around 250000 extant Species within the phylum with an estimated 70000 The name Limpet is used for many kinds of mostly saltwater but also freshwater Snails specifically those that have a simple shell which is more or less broadly conical A swimmer or diver usually performs this task. Swimming is the movement by humans or animals through Water, usually without artificial assistance This article refers to underwater diving by humans For other uses of the term diving see Dive and Diving Underwater diving is Normally they are directly attached, but the warhead of the human torpedo was linked to the magnets by wires about one foot (30 cm) long. Human torpedoes or manned torpedoes were secret naval weapons of World War II.

Usually they are set off by a time fuze. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function They may also have an anti-removal system making it explode if the mine is torn off by enemy divers or by other explosions. Sometimes the limpet mine had a small propeller which would detonate when the ship had sailed a certain distance. This ensures that the ship was likely to sink in deep water out of reach of easy salvage and makes it harder to determine the reason for the sinking. Marine salvage is the process of rescuing a ship its cargo and sometimes the crew from peril

Typically they have special compartments within them to ensure that the mine has only a slight negative buoyancy, making them easier to handle. In Physics, buoyancy ( BrE IPA: /ˈbɔɪənsi/ is the upward Force on an object produced by the surrounding liquid or gas in which it is

A British limpet mine was developed by Stuart MacRae (editor of 'Science Armchair Magazine') and Major C. V. Clarke in 1939 using improvised development techniques. ^[9][10]

An example of the use of limpet mines by British special forces was in Operation Frankton which had the objective of disabling and sinking merchant shipping moored at Bordeaux, France in 1942. Operation Frankton was a World War II British Combined Operations military Commando raid on Nazi German shipping in ( Gascon: Bordèu) is a port city in southwest France, with one million inhabitants in its metropolitan area at a 2008 estimate This article is about the country For a topic outline on this subject see List of basic France topics. The operation was also the subject of a feature film titled The Cockleshell Heroes. The Cockleshell Heroes is a 1955 Second World War Film with Trevor Howard, Anthony Newley, David Lodge The "limpets" used by the British during World War II contained only 4 kg of explosive, but placed 2 meters below the water line they caused a hole in a ship one meter wide. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including

In 1980 a limpet mine was used to sink the Sierra,^[11] a pirate whaling vessel which docked in hiding in Portugal after a confrontation with Sea Shepherd, both exposing the Portuguese government for lying to international Governments about it being a safe haven for illegal whalers and encouraging a worldwide backlash against whaling in general, later that year approximately half the Spanish whaling fleet was sunk in a similar fashion,^[12] rewards were also offered for the safe-sinking of whaling vessels by various ethical organisations. The Sea Shepherd Conservation

Another well known use was the sinking of the Rainbow Warrior by the French DGSE in Auckland harbour, New Zealand, on July 10, 1985 to prevent them bringing attention to the nuclear testing underway. The sinking of the Rainbow Warrior, codenamed Opération Satanique, was an operation by the "action" branch of the French foreign Early career The Rainbow Warrior was built in 1955 in Aberdeen, Scotland as a trawler named Sir William Hardy, and entered service with This article is about the country For a topic outline on this subject see List of basic France topics. The Auckland metropolitan area or Greater Auckland, in the North Island of New Zealand, is the largest and most populous urban area in the country New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island Events 48 BC - Battle of Dyrrhachium, Julius Caesar barely avoids a catastrophic defeat to Pompey in Macedonia. Year 1985 ( MCMLXXXV) was a Common year starting on Tuesday (link displays 1985 Gregorian calendar)

• Images of a limpet mine: [1] [2] [3]
• Image of limpet mine used in Operation Frankton

Floating contact mines

Generally, this mine type is set to float just below the surface of the water or as deep as five meters. Operation Frankton was a World War II British Combined Operations military Commando raid on Nazi German shipping in Although Australia was remote from the main battlefronts there was considerable Axis naval activity in Australian waters during World War II. A steel cable connecting the mine to an anchor on the seabed prevents them from drifting away. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 An anchor is an object often made out of metal that is used to attach a ship to the bottom of a body of water at a specific point The explosive and detonating mechanism is contained in a buoyant metal or plastic shell. The depth below the surface at which the mine floats can be set so that only deep draft vessels such as aircraft carriers, battleships or large cargo ships are at risk. By setting the depth to ten metres, this prevents a less valuable ship from detonating the mine. Similarly, in littoral waters it is important to ensure that the mine does not become visible when the sea level falls at low tide, so the preset cable length is adjusted to take account of tide variations. Littoral refers to the coast of an ocean or sea or to the banks of a river lake or estuary Even as far back as the Second World War, mines capable of being moored in 300 metres of ocean existed. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including

Generally, floating mines have a weight of around 200 kg, including 80 kg of explosives e. g. TNT, minol or amatol. Trinitrotoluene ( TNT) is a Chemical compound with the formula C6H2(NO23CH3 The VEB Kombinat Minol, founded on 1 January 1956, was the state-owned Gasoline and Lubricant reseller of the German Democratic Amatol is a highly Explosive material made from a mixture of TNT and Ammonium nitrate.

During WWII mine traps were used for blocking port entrances. Two floating mines were anchored some distance apart on either side of a shipping channel, linked by a chain. When a deep draft vessel passed through the trap, the chain would be pulled along by it, and drag both mines into opposite sides of the ship. The resulting double explosion often sank the ship. This system was not used extensively, but proved effective in blocking ports.

Drifting contact mines

Drifting mines were occasionally used during World War I and World War II. World War I (abbreviated WWI; also known as the First World War, the Great War, and the War to End All World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including However, they were more feared than effective. A drifting mine is simply a floating mine without any mooring. Sometimes floating mines break from their moorings and become drifting mines, but modern mines should be constructed to deactivate in this event. After several years at sea, the deactivation mechanism might not function as intended and the mines may remain active. Admiral Jellicoe's British fleet did not pursue and destroy the outnumbered German High Seas Fleet when it turned away at the Battle of Jutland because he thought they were leading him into a trap. Admiral of the Fleet John Rushworth Jellicoe 1st Earl Jellicoe, GCB, OM, GCVO ( 5 December 1859 &ndash 20 November fix various bugs per WikipediaHow to fix bunched-up edit links --> He believed that the Germans either were leaving floating mines in their wake, or were drawing him towards submarines. Both dangers were imaginary - the German fleet did not carry mines.

Churchill promoted "Operation Royal Marine" in 1940 and again in 1944 where floating mines were put into the Rhine in France to float down the river, becoming active after a fixed interval by which time they should have reached German territory. Operation Royal Marine was a military operation in World War II, in which Naval mines were floated down rivers from France into Germany to destroy The Rhine (Rhein Rijn Rhin Reno Rain Rhenus is one of the longest and most important Rivers in Europe at 1320 kilometres (820 mi with an average discharge

After World War I the drifting contact mine was banned, but was occasionally used during World War II. The drifting mines were much harder to remove after the war and they caused about as much damage to both sides.

These mines usually weighed 120 kg, including 80 kg of explosives (TNT).

Bottom contact mines

A bottom contact mine is the simplest form of mine. It is merely an explosive charge and a trigger lying on the seafloor. They have been used against submarines, as submarines sometimes lie on the seafloor to reduce their acoustic signature. They are also used to prevent landing craft from reaching the shore and were a major obstacle during the D-Day landings. The Germans used antitank mines here with minor modifications to make them more reliable underwater, attaching the mines to the front of many of the obstacles seen in photos of the landing.

These mines usually weighed 2 to 50 kg, including 1 to 40 kg of explosives (TNT or hexatonal). Cyclotrimethylenetrinitramine, also known as RDX, cyclonite, hexogen, and T4, is an Explosive Nitroamine widely used

Remotely controlled mines

Frequently used in combination with coastal artillery and hydrophones, remote controlled (or command detonation) mines can be in place in peacetime, which is a huge advantage in blocking important shipping routes. The mines are usually equipped to be turned into "normal" mines with a switch (which prevents the enemy from simply capturing the controlling station and deactivating the mines), detonated by hand or be allowed to detonate on their own. The earliest ones were developed around 1812 by Robert Fulton. Robert Fulton ( November 14, 1765 &ndash February 24, 1815) was a U The first use was moored mines used in the American Civil War, detonated electrically from shore. Causes of the war See also Origins of the American Civil War, Timeline of events leading to the American Civil War The coexistence of a slave-owning South These were seen as superior to contact mines because they only deprived the waterway to the enemy.

Modern examples usually weigh 200 kg (440 lb), including 80 kg (175 lb) of explosives (TNT or hexatonal).

Moored mines

The moored mine is the backbone of modern mine systems. They are deployed where water is too deep for bottom mines. Using several kinds of instruments to detect an enemy, usually a combination of acoustic, magnetic and pressure sensors. Acoustic signature is used to describe a combination of acoustic emissions of ships and submarines In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. A pressure sensor measures the Pressure, typically of Gases or Liquids. More exotic ones include optical shadows or electro potential sensors. These cost many times more than contact mines. Moored mines are effective against most kinds of ships. Being cost-efficient compared to other anti-ship weapons, they can be deployed in large numbers, making them useful area denial or "channelizing" weapons. Anti-ship missiles are a Missile designed for use against Ships Most anti-ship missiles are of the Sea-skimming type and use a combination of Area denial weapons are used to prevent an adversary from occupying or traversing an area of land Moored mines usually have lifetimes over 10 years, and some almost unlimited. These mines usually weigh 200 kg (440 lb), including 80 kg (175 lb) of explosives (hexatonal). Cyclotrimethylenetrinitramine, also known as RDX, cyclonite, hexogen, and T4, is an Explosive Nitroamine widely used In excess of 150 kg (330 lb) of explosives the mine becomes inefficient, as it becomes too large to handle and the extra explosives add little to the mine's effectiveness.

Bottom mines

Bottom mines are used when the water is no more than 60 meters (180 ft) deep or when mining for submarines down to around 200 meters (660 ft). They are much harder to detect and sweep, and can carry a much larger warhead than a moored mine. Bottom mines commonly use pressure sensitive exploders, which are less sensitive to sweeping.

These mines usually weigh between 150 and 1,500 kilograms (330 to 3,300 pounds), including between 125 and 1,400 kg (275 to 3,090 pounds) of explosives.

Influence mines

These mines are triggered by the influence of a ship or submarine, rather than direct contact. Such mines incorporate electronic sensors designed to detect the presence of a vessel and detonate when it comes within the blast range of the warhead. Electronics refers to the flow of charge (moving Electrons through Nonmetal conductors (mainly Semiconductors, whereas electrical Detonation is a process of Supersonic Combustion in which a Shock wave is propagated forward due to energy release in a reaction zone behind it An explosion is a sudden increase in Volume and release of Energy in an extreme manner usually with the generation of high Temperatures and the release Typically a warhead is the Explosive material and Detonator that is delivered by a Missile, Rocket, or Torpedo. The fuzes on such mines may incorporate one or more of the following sensors: magnetic, passive acoustic or water pressure displacement caused by the proximity of a vessel. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface

First used during the Second World War, the sophistication of influence mine fuzes has increased considerably over the years as first transistors and then microprocessors have been incorporated into designs. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function In Electronics, a transistor is a Semiconductor device commonly used to amplify or switch electronic signals A microprocessor incorporates most or all of the functions of a Central processing unit (CPU on a single Integrated Simple magnetic sensors have been superseded by total-field magnetometers. A magnetometer is a scientific instrument used to measure the strength and/or direction of the Magnetic field in the vicinity of the instrument Whereas early magnetic mine fuzes would respond only to changes in a single component of a target vessel's magnetic field, a total field magnetometer responds to changes in the magnitude of the total background field. Similarly, the original broadband hydrophones of 1940s acoustic mines (which operate on the integrated volume of all frequencies) have been replaced by narrow-band sensors which are much more sensitive and selective. A hydrophone (Greek "hydro" = "water" and "phone" = "sound" is a Microphone designed to be used underwater for recording or listening Mines can now be programmed to listen for highly specific acoustic signatures (e. Acoustic signature is used to describe a combination of acoustic emissions of ships and submarines g. a gas turbine powerplant and/or cavitation sounds from a particular design of propellor) and ignore all others. A gas turbine, also called a combustion turbine, is a rotary Engine that extracts energy from a flow of Combustion gas Cavitation is defined as the phenomenon of formation of vapour bubbles of a flowing liquid in a region where the pressure of the liquid falls below its vapour pressure A propeller is essentially a type of fan which transmits power by converting Rotational motion into Thrust for propulsion of a vehicle such as an The sophistication of modern electronic mine fuzes incorporating these Digital Signal Processing capabilities makes it much more difficult to "trick" the sensors with electronic countermeasures because the combined range of sensors working together (e. Electronics refers to the flow of charge (moving Electrons through Nonmetal conductors (mainly Semiconductors, whereas electrical Digital signal processing ( DSP) is concerned with the representation of the signals by a sequence of numbers or symbols and the processing of these signals Electronic Countermeasures ( ECM') are a subsection of Electronic warfare which includes any sort of electrical or electronic device designed to trick g. magnetic, passive acoustic and water pressure) means they are very discriminating against false inputs.

Modern influence mines are computerised, with all the programmability that this implies e. A computer is a Machine that manipulates data according to a list of instructions. g. the ability to quickly load new acoustic signatures into fuzes, or program them to detect a single, highly distinct target signature. Acoustic signature is used to describe a combination of acoustic emissions of ships and submarines In this way, a mine with a passive acoustic fuze can be programmed to ignore all friendly vessels plus small enemy vessels, only detonating when a very large enemy target passes over it. Detonation is a process of Supersonic Combustion in which a Shock wave is propagated forward due to energy release in a reaction zone behind it Alternatively, the mine can be programmed specifically to ignore all surface vessels regardless of size and exclusively target submarines. A submarine is a Watercraft that can operate independently below water as distinct from a Submersible that has only limited underwater capability

Even as far back as the Second World War it was possible to incorporate a "ship counter" facility into mine fuzes i. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including e. set the mine to ignore the first two ships to pass over it (which could be mine-sweepers deliberately trying to trigger mines) but detonate when the third ship passes overhead - which could be a high value target such as an aircraft carrier or oil tanker. A minesweeper is a Naval Warship designed to counter the threat posed by Naval mines The dedicated purpose-built minesweeper first appeared during Detonation is a process of Supersonic Combustion in which a Shock wave is propagated forward due to energy release in a reaction zone behind it An aircraft carrier is a Warship designed with History The technology of oil transportation has evolved alongside the oil industry Even though modern mines are generally powered by a long life lithium battery, it is important to conserve power because they may need to remain active for months or even years. Lithium batteries are not to be confused with lithium-ion batteries which are high energy-density rechargeable batteries Lithium batteries are For this reason, most influence mines are designed to remain in a semi-dormant state until an unpowered (e. g. deflection of a magnetic compass needle) or low-powered sensor detects the possible presence of a vessel, at which point the mine fuze powers up fully and the passive acoustic sensors will begin to operate for some minutes. A compass, magnetic compass or mariner's compass is a navigational instrument for determining direction relative to the earth's Magnetic poles It consists In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function Obviously, it is possible to program computerised mines to delay activation for days or weeks after being laid. Similarly, they can be programmed to self-destruct or render themselves safe after a preset period of time e. A self-destruct is a mechanism which causes a device to destroy itself under a predefined set of circumstances g. 12 days or 12 months. As a general rule of thumb, the more sophisticated the mine design, the more likely it is to have some form of anti-handling device fitted in order to hinder clearance by divers or remotely piloted submersibles. An Anti-handling device is an attachment to or integral part of a Landmine, designed to prevent tampering

Unusual mines

Several specialized mines have been developed for other purposes than the common minefield.

Anti sweep mine

The anti sweep mine is a very small mine (40 kg warhead) with as small a floating device as possible. When the wire of a mine sweep hits the mine, it "sinks", letting the sweep wire drag along the anchoring wire of the mine until the sweep hits the mine. That detonates the mine and cuts the sweeping wire. They are very cheap and usually used in combination with other mines in a minefield to make sweeping more difficult.

Rocket mine

A Russian invention, the rocket mine is a bottom distance mine that fires a homing high-speed rocket (not torpedo) upwards towards the target. It is intended to allow a bottom mine to attack surface ships as well as submarines from a greater depth.

Torpedo mine

The torpedo mine is a self-propelled variety, able to lie in wait for a target and then pursue it e. g. the CAPTOR mine. The CAPTOR is the United States Navy 's primary anti-submarine Naval mine. Other designs such as the Mk 67 Submarine Launched Mobile Mine [4] (which is based on a Mark 37 torpedo) are capable of swimming as far as 10 miles through or into a channel, harbor, shallow water area and other zones which would normally be inaccessible to craft laying the device. The Mark 37 torpedo is a Torpedo with electrical propulsion developed for the US Navy after World War II. After reaching the target area they sink to the sea bed and act like conventionally laid influence mines. As a general rule, torpedo mines incorporate computerised acoustic and magnetic fuzes. A computer is a Machine that manipulates data according to a list of instructions. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function

The U. S. Mark 24 "mine", code-named FIDO, was actually an ASW homing torpedo. The Mark 24 FIDO Torpedo was a US air-dropped passive acoustic homing anti- Submarine Torpedo used during the Second World War against German Anti-submarine warfare (ASW or in older form A/S is a branch of Naval warfare that uses surface Warships Aircraft, space craft or other Submarines The mine designation was disinformation to conceal its function.

Bouquet mine

The bouquet mine is a single anchor attached to several floating mines. It is designed so that when one mine is swept/detonated, another takes its place. It is a very sensitive construction and lacks reliability.

Ascending mine

The ascending mine is a floating distance mine that may cut its mooring or in some other way float higher when it detects a target. It lets a single floating mine cover a much larger depth range.

Daisy-chained mine

This comprises two moored, floating contact mines which are tethered together by a length of steel cable or chain. Typically, each mine is situated approximately 60 feet (18 m) away from its neighbour, and each floats a few metres below the surface of the ocean. When the target ship hits the steel cable, the mines on either side are drawn down the side of the ship's hull, exploding on contact. In this manner it is possible to target ships which might pass safely between two individually moored mines. Daisy-chained mines are a very simple concept which was used during the Second World War. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including

Dummy mine

Plastic drums filled with sand or concrete are periodically rolled off the side of ships as real mines are laid in large mine-fields. Concrete is a construction material composed of Cement (commonly Portland cement) as well as other cementitious materials such as Fly ash and Slag These false targets (designed to be of a similar shape and size as genuine mines) are intended to slow down the process of mine clearance: a mine-hunter is forced to investigate each suspicious sonar contact on the sea bed, whether it is real or not.

Mine laying

Historically several methods were used to lay mines. During the First and Second World Wars, the Germans used U-boats to lay mines around the UK. U-boat is the anglicized version of the German word, itself an abbreviation of Unterseeboot ( undersea boat) and refers In the Second World War, aircraft came into favour for mine laying with the one of largest such examples is the mining of the Japanese sea routes in Operation Starvation. Operation Starvation was an American mining operation conducted in World War II by the Army Air Force, in which vital water routes and ports

Laying a minefield is a relatively fast process with specialized ships, which is still today the most common method. These minelayers can carry several thousand mines and manoeuvre with high precision. Minelaying is the act of deploying explosive mines Historically this has been carried out by ships submarines and aircraft The mines are dropped at a predefined interval into the water behind the ship. Each mine is recorded for later clearing, but it is not unusual for these recordings to be lost together with the ships. Therefore many countries demand that all mining operations shall be planned on land and records kept so the mines can later be recovered more easily.

Other methods to lay minefields include:

• Converted merchant ships - rolled or slid down ramps
• Aircraft - descent to the water is slowed by a parachute
• Submarines - launched from torpedo tubes or deployed from specialized mine racks on the sides of the submarine
• Combat boats - rolled off the side of the boat
• Camouflaged boats - masquerading as fishing boats
• Dropping from the shore - typically smaller, shallow-water mines
• Attack divers - smaller shallow-water mines

In some cases, mines are automatically activated upon contact with the water. A parachute is a device used to slow the motion of an object through an atmosphere by creating drag. The modern torpedo (historically called an automotive automobile locomotive or fish torpedo is a self-propelled explosive Projectile weapon launched above or below In others, a safety lanyard is pulled (e. A lanyard, laniard, or wrist strap is a Rope or cord often worn around the Neck or Wrist to carry something g. one end attached to the rail of a ship) which starts an automatic timer countdown before the arming process is complete. Typically, the automatic safety-arming process takes some minutes to complete. This is in order to give the people laying the mines sufficient time to move out of its activation/blast zone.

Aerial mining in World War II

Germany

In the 1930s, Germany had experimented with the laying of mines by aircraft; it became a crucial element in their overall mining strategy. Aircraft had the advantage of speed, and they would never get caught in their own minefields. German mines held a large 1,000 lb. (450 kg) explosive charge. From April to June 1940, the Luftwaffe laid 1,000 mines in British waters. ( German 'luftvafe is a generic German term for an Air force. Soviet ports were mined, as was the Arctic convoy route to Murmansk. The Arctic Convoys of World War II travelled from the United Kingdom and the United States to the northern ports of the Soviet ^[13] The Heinkel He 115 could carry two medium or one large mine while the Heinkel He 59, Dornier Do 18, Junkers Ju 88 and Heinkel He 111 could carry more. The Heinkel He 115 was a World War II Luftwaffe Seaplane with three seats WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout

Soviet Union

The USSR was relatively ineffective in its use of naval mines in WWII in comparison with its record in previous wars. ^[14] Small mines were developed for use in rivers and lakes, and special mines for shallow water. A very large chemical mine was designed to sink through ice with the aid of a melting compound. Special aerial mine designs finally arrived in 1943-1944, the AMD-500 and AMD-1000. ^[15] Various Soviet Naval Aviation torpedo bombers were pressed into the role of aerial mining in the Baltic Sea and the Black Sea, including Ilyushin DB-3s, Il-4s and Lend Lease Douglas Boston IIIs. Soviet Naval Aviation ( Авиация военно-морского флота in Russian, or Aviatsiya Voenno-Morskogo Flota, literally "aviation The Baltic Sea is a Brackish inland sea located in Northern Europe, from 53°N to 66°N Latitude and from 20°E to 26°E Longitude. The Black Sea is an inland Sea bounded by southeastern Europe, the Caucasus and the Anatolian peninsula ( Turkey WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Lend-Lease (Public Law 77-11 was the name of the program under which the United States of America supplied the United Kingdom, the Soviet Union, WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout ^[16]

United Kingdom

In September 1939, the UK announced the placement of extensive defensive minefields in waters surrounding the Home Islands. Offensive aerial mining operations began in April 1940 when 38 mines were laid at each of these locations: the Elbe River, the port of Lubeck and the German naval base at Kiel. The Elbe ( die Elbe Low German: de Ilv) is one of the major Rivers of Central Europe. Lübeck ( is the second largest City in Schleswig-Holstein, in Northern Germany, and one of the major For the city in the United States, see Kiel Wisconsin. For the name see Kiel (name. In the next 20 months, mines delivered by aircraft sank or damaged 164 Axis ships with the loss of 94 aircraft. By comparison, direct aerial attacks on Axis shipping had sunk or damaged 105 vessels at a cost of 373 aircraft lost. The advantage of aerial mining became clear. The United Kingdom geared up for mining; a total of 48,000 aerial mines were laid by the Royal Air Force (RAF) in the European Theatre during World War II. The European Theatre of Operations ( ETO) was an area of heavy fighting across Europe during World War II, from Nazi Germany's Invasion of Poland ^[17]

United States

The United States's early aerial mining efforts used smaller aircraft unable to carry many mines. Using TBF Avenger torpedo bombers, the US Navy mounted a direct aerial mining attack on enemy shipping in Palau on 30 March 1944 in concert with simultaneous conventional bombing and strafing attacks. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Palau, officially the Republic of Palau (Beluu er a Belau is an island nation in the Pacific Ocean, some 500 miles (800  km) east Events 240 BC - 1st recorded Perihelion passage of Halley's Comet. Year 1944 ( MCMXLIV) was a Leap year starting on Saturday (link will display full calendar of the Gregorian calendar. The dropping of 78 mines stopped 32 Japanese ships from escaping Koror harbor; the combined operation sank or damaged 36 ships. Koror is the state comprising the main commercial center of the Republic of Palau. ^[18] Two Avengers were lost; their crews were recovered. ^[19] The mines brought port usage to a halt for 20 days; further mine-laying in the area contributed to the Japanese abandoning Palau as a base. ^[20]

As early as 1942, American mining experts such as Naval Ordnance Laboratory scientist Dr. Ellis A. Johnson, Commander, Naval Reserve, suggested massive aerial mining operations against Japan's "outer zone" (Korea and northern China) as well as the "inner zone", their home islands. The, which forms the Country of Japan, extends roughly from northeast to southwest along the northeastern coast of the Eurasia mainland washing upon the northwestern First, aerial mines would have to be developed further and manufactured in large numbers. Second, laying the mines would require a sizable air group. The US Army Air Force had the carrying capacity but considered mining to be the Navy's job. The United States Army Air Forces ( USAAF) was the military aviation arm of the United States of America during and immediately after World War II. The US Navy lacked suitable aircraft. Johnson set about convincing General Curtis LeMay of the efficacy of very heavy bombers laying aerial mines. Curtis Emerson LeMay (15 November 1906–3 October 1990 was a General in the United States Air Force and the vice presidential running mate of American Independent ^[21]

In the meantime, B-24 Liberator, PBY Catalina and other available bomber aircraft took part in localized mining operations in the Southwest Pacific and the China Burma India (CBI) Theaters, beginning with a very successful attack on the Yangon River in February 1943. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout The South West Pacific was one of two theatres of World War II in the Pacific region between 1942 and 1945. China Burma India Theater (CBI (later IBT or India-Burma theater was the name used by the United States Army for its forces operating in conjuction with Allied air The Yangon River (also known as Rangoon River or Hlaing River) is an Estuary that runs from Yangon to the Andaman Sea. Aerial minelaying operations involved a coalition of British, Australian and American aircrews, with the RAF and the Royal Australian Air Force (RAAF) carrying out 60% of the sorties and the USAAF and US Navy covering 40%. The Royal Australian Air Force ( RAAF) is the Air Force branch of the Australian Defence Force. Both British and American mines were used. Japanese merchant shipping suffered tremendous losses, while Japanese mine sweeping forces were spread too thin attending to far-flung ports and extensive coastlines. Admiral Thomas C. Kinkaid, who directed nearly all RAAF mining operations in CBI, heartily endorsed aerial mining, writing in July 1944 that "aerial mining operations were of the order of 100 times as destructive to the enemy as an equal number of bombing missions against land targets. Thomas Cassin Kinkaid ( 3 April 1888 &ndash 17 November 1972) was an Admiral of the United States Navy during World "^[22]

Finally, in March 1945, Operation Starvation began in earnest, using 160 of LeMay's B-29 Superfortress bombers to attack Japan's inner zone. Operation Starvation was an American mining operation conducted in World War II by the Army Air Force, in which vital water routes and ports Almost half of the mines were the US-built Mark 25 model, carrying 1250 lbs of explosives and weighing about 2,000 lbs. Other mines used included the smaller 1,000 lb Mark 26. ^[23] 15 B-29s were lost while 293 enemy merchant ships were sunk or damaged. ^[24] 12,000 aerial mines were laid, a significant barrier to Japan's access to outside resources. Prince Fumimaro Konoe said after the war that the aerial mining by B-29s had been "equally as effective as the B-29 attacks on Japanese industry at the closing stages of the war when all food supplies and critical material were prevented from reaching the Japanese home islands. Fumimaro Konoe 3rd Prince Konoe ( Kyūjitai: 近衞 文麿 Shinjitai: 近衛 文麿 Konoe Fumimaro) ( sometimes Konoye, October 12 "^[25] The United States Strategic Bombing Survey (Pacific War) concluded that it would have been more efficient to combine the United States's effective anti-shipping submarine effort with land- and carrier-based air power to strike harder against merchant shipping and begin a more extensive aerial mining campaign earlier in the war. The "Strategic bombing survey (Pacific War" was a United States Army Air Forces report on the impact of Strategic bombing in World War II in The Pacific War was the part of World War II —and preceding conflicts—that took place in the Pacific Ocean, its islands and in East Asia, between Survey analysts projected that this would have starved Japan, forcing an earlier end to the war. ^[26] After the war, Dr. Johnson looked at the Japan inner zone shipping results, comparing the total economic cost of submarine-delivered mines versus air-dropped mines and found that, though 1 in 12 submarine mines connected with the enemy as opposed to 1 in 21 for aircraft mines, the aerial mining operation was about ten times less expensive per enemy ton sunk. ^[27]

Clearing WWII aerial mines

Between 600,000 and 1,000,000 naval mines of all types were laid in World War II. Advancing military forces worked to clear mines from newly-taken areas, but extensive minefields remained in place after the war. Air-dropped mines had an additional problem for mine sweeping operations: they weren't meticulously charted. In Japan, much of the B-29 mine-laying work had been performed at high altitude, with the drifting on the wind of mines carried by parachute adding a randomizing factor to their placement. Generalized danger areas were identified, with only the quantity of mines given in detail. Mines used in Operation Starvation were supposed to be self-sterilizing, but the circuit did not always work. Clearing the mines took so many years that the task was eventually given to the Japan Maritime Self-Defense Force. The, or JMSDF, is the maritime branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. ^[28]

Damage

The damage that may be received from a mine depends on the distance that the target is away from the area of detonation. The amount of damage that a ship takes is not always directly connected to the explosive physical impact of the mine.

Direct damage

Usually only created by contact mines, direct damage is a hole blown in the ship. Among the crew, shrapnel wounds are the most common form of damage. This rarely sinks the ship, but might flood one or two compartments – usually in the bow.

Bubble jet effect

The bubble jet effect occurs when a mine detonates in the water some distance away from the ship. The explosion creates a "hole" in the water, and due to the difference in pressure, this sphere will collapse from the bottom. This creates a "pillar" of water that can go over a hundred meters into the air. The damage to the ship is heavy. The water breaks a meter wide hole straight through the ship, flooding one or more compartments, and might break the ship apart. The crew in the areas hit by the pillar are usually killed instantly. Other damage is usually limited.

Shaking effect

If the mine detonates at a distance from the ship, the change in water pressure causes the ship to resonate. This is frequently the most deadly type of explosion, if strong enough. The whole ship is dangerously shaken and everything onboard is tossed around. Engines rip from their beds, cables from their holders, etc. A badly shaken ship usually sinks quickly, with hundreds, or even thousands of small leaks all over the ship and no way to power the pumps. The crew fare no better, as the violent shaking tosses them around.

• Photos of damage done to the USS Samuel B. Roberts (FFG 58) by an Iranian M-08 moored mine in 1988. Commissioning and namesake The frigate was named for Samuel B

Countermeasures

Weapons are frequently a few steps ahead of countermeasures, and mines are no exception. In this field the British, with their large sea-going navy, have had the bulk of world experience, and most anti-mine developments, such as de-gaussing and the double-L sweep were British inventions. When on operational missions, such as the recent invasion of Iraq, the US still rely on British and Canadian minesweeping services. The US have worked on some innovative mine hunting countermeasures, such as the use of military dolphins to detect and flag mines. A military dolphin is a Cetacean trained for military uses The United States and Russian militaries have trained and employed Oceanic dolphins However, they are of questionable effectiveness.

Passive countermeasures

By building ships with as low signature as possible one can avoid detonating mines. This is especially true for minesweepers and mine hunters that work in minefields. These ships are built out of glass fibre or even wood instead of steel to avoid magnetic signatures, they use special propulsion systems, such as Voith-Schneider propellers, to limit the acoustic signature. The Voith Schneider Propeller (VSP also known as a cycloidal drive is a specialized marine propulsion system Acoustic signature is used to describe a combination of acoustic emissions of ships and submarines They are built with hulls that produce a minimal pressure signature. These measures create other problems. They are expensive, slow, and vulnerable to enemy fire. Therefore, they need protection. Many modern ships have a mine warning sonar—a simple sonar looking forward and warning the crew if it detects possible mines ahead. Sonar (which started as an Acronym for sound navigation and ranging) is a technique that uses Sound propagation (usually underwater to navigate It is only effective when moving slowly.

A steel-hulled ship can be degaussed (more correctly, deoerstedted or depermed) using a special degaussing station that contains many large coils and induces a magnetic field in the hull with alternating current to demagnetize the hull. Deperming is a procedure for erasing the permanent magnetism from ships and Submarines to Camouflage them against magnetic detection vessels and enemy marine This is a rather problematic solution, as magnetic compasses need recalibration and all metal objects must be kept in exactly the same place. Ships slowly regain their magnetic field as they travel through the Earth's magnetic field, so the process has to be repeated every six months.

A variation on this technique, called wiping, was developed by Dr. Charles F. Goodeve, RCNVR, which saved time and resources. Charles Frederick Goodeve ( 21 February 1904 – 7 April 1980) was a Canadian Chemist and pioneer in Operations research The Royal Canadian Navy Volunteer Reserve (RCNVR was a naval reserve force of the Royal Canadian Navy, which replaced the Royal Navy Canadian Volunteer Reserve

Between 1941 and 1943 the US Naval Gun factory (a division of the Naval Ordinance Laboratory) in Washington D. C. built physical models of all US Naval ships. Three kinds of steel were used in shipbuilding: mild steel for bulkheads, a mixture of mild steel and high tensile steel for the hull, and special treatment steel for armor plate. The models were placed within coils which would simulate the earth's magnetic field at any location. The magnetic signatures were measured with degaussing coils. The objective was to reduce the vertical component of the Earth's field combined with the ships field at the usual depth of German mines. From the measurements, coils were placed and coil currents determined to minimize the chance of detonation for any ship at any heading at any latitude.

Some ships are built with magnetic inductors, large coils placed along the ship to counter the ship's magnetic field. Using magnetic probes in strategic parts of the ship, the strength of the current in the coils can be adjusted to minimize the total magnetic field. This is a heavy and clumsy solution, suited only to smaller ships.

Active countermeasures

Active countermeasures are ways to clear a path through a minefield or remove it completely. This is one of the most important tasks of any mine warfare flotilla.

Mine sweeping

A sweep is either a contact sweep, a wire dragged through the water by one or two ships to cut the mooring wire of floating mines, or a distance sweep that mimics a ship to detonate the mines. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Helicopter Mine Countermeasures Squadron 15 (HM-15 is a United States Navy helicopter squadron based at Naval Air Station Corpus Christi, Texas. The sweeps are dragged by minesweepers, either military ships or converted trawlers. A minesweeper is a Naval Warship designed to counter the threat posed by Naval mines The dedicated purpose-built minesweeper first appeared during Each run covers between one and two hundred meters, and the ships must move slowly in a straight line, making them vulnerable to enemy fire. This was exploited by the Turkish army in the Battle of Gallipoli in 1915, when mobile howitzer batteries prevented the British and French from clearing a way through minefields. A howitzer is a type of Artillery piece that is characterized by a relatively short barrel and the use of comparatively small explosive charges to propel projectiles

If a contact sweep hits a mine, the wire of the sweep rubs against the mooring wire until it is cut. Sometimes "cutters", explosive devices to cut the mine's wire, are used to lessen the strain on the sweeping wire. Mines cut free are recorded and collected for research or shot with a deck gun.

Minesweepers protect themselves with an oropesa or paravane instead of a second minesweeper. An Oropesa is a streamlined towed body used in the process of minesweeping. The paravane is a form of towed underwater "glider" It was developed by Cdr Usborne and Lt Burney financed by Sir George White founder of the Bristol Aeroplane These are torpedo-shaped towed bodies, similar in shape to a Harvey Torpedo, that are streamed from the sweeping vessel thus keeping the sweep at a determined depth and position. Some large warships were routinely equipped with paravane sweeps near the bows in case they inadvertently sailed into minefields — the mine would be deflected towards the paravane by the wire instead of towards the ship by its wake. More recently, heavy-lift helicopters have dragged minesweeping sleds, as in the 1991 Persian Gulf War.

The distance sweep mimics the sound and magnetism of a ship and is pulled behind the sweeper. It has floating coils and large underwater drums. It is the only sweep effective against bottom mines.

During the Second World War, RAF Coastal Command used Vickers Wellington bombers fitted with degaussing coils to trigger magnetic mines. RAF Coastal Command was an organization within the Royal Air Force which defended the United Kingdom from naval threats and countered German U-boats WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout

Modern influence mines have the ability to discriminate against false inputs and are therefore much harder to sweep. They often contain inherent anti-sweeping mechanisms. For example, they may be programmed to respond to the unique noise of a particular ship-type, its associated magnetic signature and the typical pressure displacement of such a vessel. As a result, a mine-sweeper must accurately guess and mimic the required target signature in order to trigger detonation. The task is complicated by the fact that an influence mine may have one or more of a hundred different potential target signatures programmed into it.

Another anti-sweeping mechanism is a ship-counter in the mine fuze. When enabled, this only allows detonation after the mine fuze has been triggered a pre-set number of times. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function To further complicate matters, influence mines may be programmed to arm themselves (or disarm automatically - known as self-sterilization) after a pre-set time. Obviously, during the pre-set arming delay (which could last days or even weeks) the mine would remain dormant and completely ignore any target stimulus, whether it was genuine or faked.

When influence mines are laid in an ocean minefield, they may have various combinations of fuze settings configured. For example, some mines (with the acoustic sensor enabled) may become active within three hours of being laid, others (with the acoustic and magnetic sensors enabled) may become active after two weeks, but have the ship counter mechanism set to ignore the first two trigger events, and still others in the same minefield (with the magnetic and pressure sensors enabled) will not become armed until three weeks have passed. Naturally, groups of mines within this mine-field can have different target signatures programmed into them which may or may not have a degree of overlap in them. Suffice to say the fuzes on influence mines allow many different permutations, which complicates the clearance process.

Using ship-counters, arming delays and highly specific target signatures in mine fuzes can create a dangerous illusion for mariners in shipping lanes i. e. that mines do not exist in a particular area (because a succession of vessels have already passed through safely) or alternatively that recent mine-sweeping operations have been successful and all mines in the zone have been located and cleared.

Mine hunting

Mine hunting is very different from sweeping, even if some minehunters can do both tasks. List of German ships All active ships are currently stationed in Kiel at the Baltic Sea. The German Navy ( Deutsche Marine ( is the Navy of Germany and part of the Bundeswehr (German Armed Forces Minehunters are mine countermeasure vessels that actively detect and destroy individual Naval mines Minesweepers on the other hand clear mined areas as a whole When mine hunting, the mines are located using sonar, then inspected and destroyed either by divers or ROVs (remote controlled unmanned mini submarines). Remotely operated underwater vehicles (ROVs is the common accepted name for tethered underwater Robots in the offshore industry It is slow, but also the most secure way to remove mines. Mine hunting started during the Second World War, but it was only after the war that it became a truly effective method.

Sea mammals (mainly the Bottlenose Dolphin) have also been trained to hunt and mark mines, most famously by the U.S. Navy Marine Mammal Program. The Bottlenose Dolphin is one of the most common and well-known Dolphins. The US Navy Marine Mammal Program ( NMMP) is a program administered by the U Mine-clearance dolphins were deployed in the Persian Gulf during the Iraq War in 2003. The Persian Gulf, in the Southwest Asian region is an extension of the The Iraq War, also known as the Second Gulf War, the Occupation of Iraq, or the War in Iraq, is an ongoing Military campaign The Navy claims that these dolphins were effective in helping to clear more than 100 antiship mines and underwater booby traps from the port of Umm Qasr. A booby trap is a device set up to be triggered by an unsuspecting victim Umm Qasr (أم قصر also Transliterated as: Um-qasir, Um-qasser) is a Port city in southern Iraq. ^[29] Needless to say, animal rights activists have depreciated the practice, some complaining that dolphins are in fact "our betters" and should not be risked to save the lives of humans, particularly humans who wage war and knowingly take war's risks. "Animal liberation" redirects here for other uses see Animal liberation (disambiguation.

French naval officerJacques Yves Cousteau's Undersea Research Group was once involved in mine-hunting operations: They removed or detonated a variety of German mines, but one particularly nasty batch—equipped with acutely sensitive pressure, magnetic, and acoustic sensors and wired together so that one explosion would trigger the rest—was simply left undisturbed for years until corrosion would (hopefully) disable the mines. Jacques-Yves Cousteau ( 11 June 1910 – 25 June 1997) was a French naval officer explorer, Ecologist, ^[30])

Mine breaking

A more drastic method is simply to take a cargo ship, load her with cargo that makes her less vulnerable to sinking (wood for example) and drive her through the minefield, letting the ship to be protected follow the same path. This method was employed by the German Kriegsmarine during WWII, using converted ships known as Sperrbrecher. Alternatively, a shallow draught vessel can be steamed through the minefield at high speed to generate a pressure wave sufficient to trigger mines, with the minesweeper moving fast enough to be sufficiently clear of the pressure wave so that triggered mines do not destroy the ship itself. These techniques are the only way to sweep pressure mines. The technique can be simply countered by use of a ship-counter, set to allow a certain number of passes before the mine is actually triggered. Modern doctrine calls for ground mines to be hunted rather than swept.

An updated form of mine breaking is the use of small unmanned ROVs that simulate the acoustic and magnetic signatures of larger ships and are built to survive exploding mines. Seehund ROV Length 25 m Displacement 99 t Propulsion Schottel Z-drive Max speed 9-10 kn Seehund The German Navy ( Deutsche Marine ( is the Navy of Germany and part of the Bundeswehr (German Armed Forces Remotely operated underwater vehicles (ROVs is the common accepted name for tethered underwater Robots in the offshore industry Repeated sweeps would be required in case one or more of the mines had its "ship counter" facility enabled i. e. were programmed to ignore the first 2, 3, or even 6 target activations.

National arsenals

US Mines

The United States Navy MK56 ASW mine (the oldest still in use by the US) was developed in 1966. The United States of America —commonly referred to as the More advanced mines include the MK60 CAPTOR (short for "encapsulated torpedo"), the MK62 and MK63 Quickstrike and the MK67 SLMM (Submarine Launched Mobile Mine). The CAPTOR is the United States Navy 's primary anti-submarine Naval mine. Today, most U. S. naval mines are delivered by aircraft.

MK67 SLMM Submarine Launched Mobile Mine
The SLMM was developed by the United States as a submarine deployed mine for use in areas inaccessible for other mine deployment techniques or for covert mining of hostile environments. The SLMM is a shallow-water mine and is basically a modified Mark 37 torpedo. The Mark 37 torpedo is a Torpedo with electrical propulsion developed for the US Navy after World War II.

General characteristics

• Type: Submarine-laid bottom mine
• Detection System: Magnetic/seismic/pressure target detection devices (TDDs)
• Dimensions: 485 mm by 4. 09 m (19 by 161 in)
• Depth Range: Shallow water
• Weight: 754 kg (1658 lb)
• Explosives: 230 kg (510 lb) high explosive
• Date Deployed: 1987

MK65 Quickstrike
The Quickstrike[5] is a family of shallow-water aircraft-laid mines used by the United States, primarily against surface craft. The MK65 is a 2,000-lb (900 kg) dedicated, purpose-built mine. However, other Quickstrike versions (MK62, MK63, and MK64) are converted general-purpose bombs. These latter three mines are actually a single type of electronic fuze fitted to Mk82, Mk83 and Mk84 air-dropped bombs. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function The Mark 82 (Mk 82 is an unguided low- drag General-purpose bomb ( Dumb bomb) part of the U The Mark 83 is part of the Mark 80 series of low- drag General-purpose bombs in United States service The Mark 84 is an American General-purpose bomb, the largest of the Mark 80 series of weapons Because this latter type of Quickstrike fuze only takes up a small amount of storage space compared to a dedicated sea mine, the air-dropped bomb casings have dual purpose i. e. can be fitted with conventional contact fuzes and dropped on land targets, or have a Quickstrike fuze fitted which converts them into sea mines. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function

General characteristics

• Type: aircraft-laid bottom mine
• Detection System: Magnetic/seismic/pressure target detection devices (TDDs)
• Dimensions: 740 mm by 3. 25 m (29 by 128 in)
• Depth Range: Shallow water
• Weight: 1086 kg (2390 lb)
• Explosives: Various loads
• Date Deployed: 1983

MK56
General characteristics

• Type: Aircraft laid moored mine
• Detection System: Total field magnetic exploder
• Dimensions: 570 mm by 2. 9 m (22. 4 by 114. 3 in)
• Depth Range: Moderate depths
• Weight: 909 kg (2000 lb)
• Explosives: 164 kg (360 lb) HBX-3
• Date Deployed: 1966

Royal Navy

According to a statement made to the UK Parliament in 2002:^[31]

". . . the Royal Navy does not have any mine stocks and has not had since 1992. Notwithstanding this, the United Kingdom retains the capability to lay mines and continues research into mine exploitation. Practice mines, used for exercises, continue to be laid in order to retain the necessary skills".

However, a British company (BAE Systems) does manufacture the 'Stonefish' influence mine for export[6] to friendly countries such as Australia, which has both war stock and training versions. BAE Systems plc (BAE is a British defence and aerospace company headquartered in Farnborough, England, that has global interests particularly For a topic outline on this subject see List of basic Australia topics. The computerised fuze on a Stonefish mine contains acoustic, magnetic and water pressure displacement target detection sensors. A computer is a Machine that manipulates data according to a list of instructions. In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface Stonefish can be deployed by fixed-wing aircraft, helicopters, surface vessels and submarines. A optional kit is available to allow Stonefish to be air-dropped, comprising an aerodynamic tail-fin section and parachute pack to retard the weapon's descent. A parachute is a device used to slow the motion of an object through an atmosphere by creating drag. The operating depth of Stonefish ranges between 30 and 200 metres. The mine weighs 990 kilograms and contains a 600 kilogram aluminised PBX explosive warhead. WikipediaNaming A polymer-bonded explosive, also called PBX or plastic-bonded explosive, is an Explosive material in which explosive powder is bound together in a matrix Typically a warhead is the Explosive material and Detonator that is delivered by a Missile, Rocket, or Torpedo. The shelf life of a Stonefish mine is 20 years, and it has an operational lifetime of 700 days after being deployed on the seabed. Stonefish incorporates arming delays, ship counting and self-sterilisation features which can be configured by the user.

See also

• Royal Navy's Admiralty Mining Establishment
• Land mine
• HMHS Britannic

References

Sources

• MacRae, Stuart (1971). Winston Churchill's Toyshop. Roundwood Press. SBN 900093-22-6.  
• Needham, Joseph (1986). Science and Civilization in China: Volume 5, Part 7. Taipei: Caves Books, Ltd.
• WW2 People's War - An archive of World War Two memories - written by the public, gathered by the BBC. BBC. Retrieved on 2007-02-19. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 197 - Roman Emperor Septimius Severus defeats usurper Clodius Albinus in the Battle of Lugdunum

Further reading

• Hartmann, Gregory K. with Scott C. Truver (1991). Weapons That Wait: Mine Warfare in the U. S. Navy. Annapolis: Naval Institute Press. ISBN 0-87021-753-4.   (Canonical general text about U. S. mine warfare)
• Hewitt, James Terrance (1998). Desert Sailor: A War of Mine. Clementsport: The Canadian Peacekeeping Press. ISBN 1-896551-17-3.   (Personal account of mine countermeasures operations in Operation Desert Storm during the Gulf War 1991, including the mining of USS Tripoli. )
• Peniston, Bradley (2006). No Higher Honor: Saving the USS Samuel B. Roberts in the Persian Gulf. Annapolis: Naval Institute Press. ISBN 1-59114-661-5.   (Describes mine damage to a U. S. frigate)
• Wise, Harold Lee (2007). Inside the Danger Zone: The U.S. Military in the Persian Gulf 1987-88. Annapolis: Naval Institute Press. ISBN 1-59114-970-3.   (Describes American efforts to combat Iranian mine campaign in the Persian Gulf)

External links

• Technical details of German Second World War sea mines
• 'Manta' & 'Murena' - two modern Italian influence mines
• 'Stonefish' - a British influence mine
• Henry Norton Sulivan : a depiction of early Naval Mine
• Our Sailors by W.H.G. Kingston
• W.L.Clowes in 1855

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