NationMaster - Encyclopedia: Hertz horns

A naval mine is a self-contained explosive device placed in water to destroy ships or submarines. Unlike depth charges, they are deposited and left to wait until they are triggered by the approach of an enemy ship. Naval mines can be used offensively, to hamper enemy ships or lock them into a harbor; or defensively, to protect friendly ships and create "safe" zones. This article is concerned solely with chemical explosives. ... German UC-1 class World War I submarine A model of Gunter Priens Unterseeboot 47 (U-47), German WWII Type VII diesel-electric hunter-killer (SSK) submarine USS Virginia, a Virginia-class nuclear attack (SSN) submarine A submarine is a specialized watercraft that can operate underwater. ... Depth Charge used by U.S. Navy later in World War II The depth charge is the oldest anti-submarine weapon. ...

Mines can be very cost-effective; inexpensive variants can cost in the range of a thousand U.S. dollars or so. Sophisticated mines can cost millions of U.S. dollars, be equipped with several kinds of sensors, and deliver a warhead by rocket or torpedo.

Polish wz. 08/39 contact mine in the open-air museum of naval equipment in Hel, Poland. The protuberances around the top of the mine, called Hertz horns, are part of the detonation mechanism.

Download high resolution version (800x692, 118 KB)wz. ... Download high resolution version (800x692, 118 KB)wz. ... Motto: none Voivodship Pomeranian Municipal government Rada Miasta Helu Mayor MirosÅ‚aw WÄ…doÅ‚owski Area 21,3 kmÂ² Population - city - urban - density 4 874 (2001) none /kmÂ² Founded City rights prior to 1198 13th century (conf. ...

Early history

The English may have used the first naval mines in 1627 at the Siege of La Rochelle, where they launched "floating petards" unsuccessfully against the French navy. Cardinal Richelieu at the Siege of La Rochelle, Henri Motte, 1881. ... The French Navy (Marine Nationale) is the maritime arm of the French military and is the largest Western European navy in terms of personnel with 45,600 personnel (the United Kingdoms Royal Navy has 43,530). ...

However, an American, David Bushnell invented the first practical 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. It was detonated by a percussion lock if it struck a ship. A cross-section sketch of Bushnells Turtle. ... The American Revolutionary War (1775–1783), also known as the American War of Independence, was a war fought primarily between Great Britain and revolutionaries within thirteen of her North American colonies. ... Smokeless powder Gunpowder, whether black powder or smokeless powder, is a substance that burns very rapidly, releasing gases that act as a propellant in firearms. ...

The American Civil War saw the first successful use of mines, by both sides. The first ship sunk by a mine was the USS Cairo in 1862 in the Yazoo River. Rear Adm. David Farragut's famous statement, "Damn the torpedoes, full speed ahead!" refers to a minefield laid at Mobile, Alabama. Combatants Union (remaining U.S. states) Confederate States of America Commanders Abraham Lincolnâ€ Ulysses S. Grant Jefferson Davis Robert E. Lee Strength 2,200,000 1,064,000 Casualties KIA: 110,000 Total dead: 360,000 Wounded: 275,200 KIA: 94,000 Total dead: 258,000 Wounded: 137,000+ The... USS Cairo, an ironclad river gunboat, was built in 1861 by James Eads and Co. ... hTe Yazoo River is a river in the U.S. state of Mississippi and the second longest tributary of the Mississippi River that flows into that river from the east (the longest is the Ohio River). ... Admiral David Glasgow Farragut David Glasgow Farragut (July 5, 1801 - August 14, 1870) was an admiral of the United States Navy during the American Civil War. ... Motto: Nickname: The Azalea City Map Political Statistics Founded 1702 Incorporated 1814 Mobile County Mayor Sam Jones Geographic Statistics Area - Total - Land - Water 412. ...

In the 19th century, mines were called torpedoes, a name likely conferred by Robert Fulton after a fish that 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. The H. L. Hunley used one to sink USS Housatonic on February 17, 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" 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. A torpedo in Rail terminology refers to a small explosive device strapped to the top of the rail to alert an approaching train of immediate danger ahead. ... Robert Fulton Robert Fulton (November 14, 1765 â€“ February 24, 1815) was a U.S. engineer and inventor, who was widely and erroneously credited with developing the first steam-powered ship. ... Families Narcinidae Torpedinidae If you came here looking for information about a fictional energy weapon, see raygun. ... Sign warning of possible electric shock hazard An electric shock can occur upon contact of a human or animal body with any source of voltage high enough to cause sufficient current flow through the muscles or nerves. ... 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. ... H. L. Hunley was a submarine of the Confederate States Navy that demonstrated both the advantages and the dangers of undersea warfare. ... USS Housatonic was a screw sloop-of-war of the United States Navy, named for one of the rivers of New England which rises in Berkshire County, Massachusetts, and flows southward into Connecticut before emptying into Long Island Sound a little east of Bridgeport, Connecticut. ... February 17 is the 48th day of the year in the Gregorian calendar. ... 1864 (MDCCCLXIV) was a leap year starting on Friday (see link for calendar) of the Gregorian calendar or a leap year starting on Sunday of the 12-day-slower Julian calendar. ... The Royal Navy of the United Kingdom is the senior service of the British armed services being the oldest of its three branches. ...

The mine's next major use came in the Russo-Japanese War in 1904, where the Russian battleship Petropavlovsk was sunk, killing the fleet commander, Admiral Makaroff, and most of the crew. On the other side, two Japanese battleships were sunk by Russian mines in just one day. Insert non-formatted text here Combatants Imperial Russia Empire of Japan Strength 500,000 Soldiers 400,000 Soldiers Casualties 25,331 Killed 146,032 Wounded 47,387 Killed 173,425 Wounded Greater Manchuria, Russian (outer) Manchuria is region to upper right in lighter Red; Liaodong Peninsula is the wedge extending... Petropavlovsk can refer to: Petropavlovsk (or Petropavl) in Kazakhstan Petropavlovsk-Kamchatsky in Russia This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

Many of the early mines were extremely fragile and dangerous to handle, with glass containers filled with nitroglycerin or mechanical devices that activated them upon tipping. Several mine laying ships were destroyed when their cargo exploded. Nitroglycerin, also known as nitroglycerine, trinitroglycerin, and glyceryl trinitrate, is a chemical compound. ...

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 cheap compared to any other anti-ship weapon and still very effective, both as a terror weapon and to sink enemy ships. Contact mines have 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. 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. This energizes the battery, which detonates the explosive. Sulfuric acid (British English: sulphuric acid), H2SO4, is a strong mineral acid. ... This article or section does not cite its references or sources. ...

Earlier form of the detonator used a vial filled with sulfuric acid, surrounded by the mixture of potassium perchlorate and sugar; when the vial was crushed, the acid ignited the perchlorate-sugar mix, and the resulting flame ignited the gunpowder charge. Potassium perchlorate, chemical formula KClO4, is a strong oxidizer. ... Magnified view of refined sugar crystals. ...

Floating mine dump at Inverness in World War I, destined for the Northern Barrage.

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. As the submarine could be at any depth down to the seabed, an American invention, the antenna mine, was widely used. 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. World War I mine dump at Inverness This image was scanned from a public domain text by the Great War Primary Documents Archive and is made available by them for any purpose provided that they are credited and a link is given to the Photos of the Great War page... World War I mine dump at Inverness This image was scanned from a public domain text by the Great War Primary Documents Archive and is made available by them for any purpose provided that they are credited and a link is given to the Photos of the Great War page... Inverness (Inbhir Nis in Scottish Gaelic) is the only city in the Scottish Highlands. ... Combatants Allies: Serbia, Russia, France, Romania, Belgium, British Empire, United States, Italy, and others Central Powers: Germany, Austria-Hungary, Bulgaria, Ottoman Empire Casualties Military dead:5 million Civilian dead:3 million Total dead:8 million Military dead:4 million Civilian dead:3 million Total dead:7 million The First World... Combatants Allies: Serbia, Russia, France, Romania, Belgium, British Empire, United States, Italy, and others Central Powers: Germany, Austria-Hungary, Bulgaria, Ottoman Empire Casualties Military dead:5 million Civilian dead:3 million Total dead:8 million Military dead:4 million Civilian dead:3 million Total dead:7 million The First World... Satellite view of the English Channel Map of the English Channel The English Channel (French: La Manche (IPA: ) is the part of the Atlantic Ocean that separates the island of Great Britain from northern France and joins the North Sea to the Atlantic. ... The North Sea is a sea of the Atlantic Ocean, located between the coasts of Norway and Denmark in the east, the coast of the British Isles in the west, and the German, Dutch, Belgian and French coasts in the south. ... German UC-1 class World War I submarine A model of Gunter Priens Unterseeboot 47 (U-47), German WWII Type VII diesel-electric hunter-killer (SSK) submarine USS Virginia, a Virginia-class nuclear attack (SSN) submarine A submarine is a specialized watercraft that can operate underwater. ...

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. A swimmer or diver usually performs this task. They are set off by a time fuze. 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. Classes Caudofoveata Aplacophora Polyplacophora Monoplacophora Bivalvia Scaphopoda Gastropoda Cephalopoda â€ Rostroconchia The mollusks or molluscs are the large and diverse phylum Mollusca, which includes a variety of familiar creatures well-known for their decorative shells or as seafood. ... Genera Acmaea Bathyacmaea Lottia Notoacmea Pectinodonta Problacmaea Limpets are marine mollusks in the family Acmaeidae with flattened, cone-shaped shells. ... Swimming is the method by which humans (or other animals) move themselves through water. ... A diver is an person who practices scuba diving or surface supplied diving. ... In an explosive device, a fuse (or fuze) is the part of the device that causes it to function. ... CGI image of two frogmen with Siebe Gorman CDBA rebreathers riding a human torpedo. ...

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 is an upward force on an object immersed in a fluid (i. ...

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. The operation was also the subject of a feature film titled The Cockleshell Heroes. During World War II, Operation Frankton was a British Combined Operations raid on shipping in Bordeaux harbour, France in December, 1942, by 12 men of the Boom Patrol Detachment, Royal Navy, in two-man Cockle MK II kayaks, (*the Cockleshell Heroes). ... City motto: Lilia sola regunt lunam undas castra leonem. ... The Cockleshell Heroes is a 1955 2nd World War film with Trevor Howard, Antony Newley and JosÃ© Ferrer, who also directed. ...

Another well known use was the sinking of the Rainbow Warrior by the French DGSE in Auckland harbour, New Zealand, on July 10, 1985. This was a standard covert use of mines. The sinking of the Rainbow Warrior, codenamed Operation SATANIC, was a special operation by the action branch of the French foreign intelligence services, the Direction GÃ©nÃ©rale de la SÃ©curitÃ© ExtÃ©rieure (DGSE), carried out on July 10, 1985. ... Rainbow Warrior II Rainbow Warrior is the name of a series of ships operated by Greenpeace. ... The Direction Générale de la Sécurité Extérieure (generally known as DGSE) is Frances external intelligence agency. ... The Auckland Metropolitan Area, or Greater Auckland, in the North Island of New Zealand, is the largest urban area in New Zealand. ... July 10 is the 191st day (192nd in leap years) of the year in the Gregorian Calendar, with 174 days remaining. ... This article is about the year. ...

Floating contact mines

The original mine type floats anywhere from just below the surface of the water to several hundred meters down. A cable connecting the mine to an anchor on the seabed prevents them from drifting away. The explosive and detonating mechanism is contained in a metal or plastic shell, which also has considerable buoyancy. 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. This is useful to avoid having a "less valuable" ship detonate the mines. A ships or boats anchor is used to attach the vessel to the bottom at a specific point. ...

These mines usually have a weight of 200 kg, including 80 kg of explosives (TNT). Trinitrotoluene (TNT, or Trotyl) is a pale yellow crystalline aromatic hydrocarbon compound that melts at 354 K (178 Â°F, 81 Â°C). ...

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 kind of system was not used extensively but proved to be effective in blocking ports.

Drifting contact mines

Drifting mines were occasionally used during World War I and World War II. However, they were more feared than effective. A drifting mine is simply a floating mine without any mooring. Sometimes floating mines rip their moorings and become drifting mines, but modern mines should be constructed to deactivate themselves if this happens. However, 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. 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 any mines. Combatants Allies: Serbia, Russia, France, Romania, Belgium, British Empire, United States, Italy, and others Central Powers: Germany, Austria-Hungary, Bulgaria, Ottoman Empire Casualties Military dead:5 million Civilian dead:3 million Total dead:8 million Military dead:4 million Civilian dead:3 million Total dead:7 million The First World... Combatants Allies: Poland, British Commonwealth, France/Free France, Soviet Union, United States, China, and others Axis Powers: Germany, Italy, Japan, and others Casualties Military dead: 17 million Civilian dead: 33 million Total dead: 50 million Military dead: 8 million Civilian dead: 4 million Total dead: 12 million World War II... Combatants United Kingdom of Great Britain and Ireland German Empire Commanders Sir John Jellicoe, Sir David Beatty Reinhard Scheer, Franz von Hipper Strength 28 battleships, 9 battlecruisers, 8 armoured cruisers, 26 light cruisers, 78 destroyers 16 battleships, 5 battlecruisers, 6 pre-dreadnoughts, 11 light cruisers, 61 torpedo-boats Casualties 6...

Churchill promoted "Operation 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 Marine was a military operation in World War II. Promoted by Winston Churchill, the concept employed floating naval mines which were dropped into the Rhine River in France. ... Loreley At 1,320 kilometres (820 miles) and an average discharge of more than 2,000 cubic meters per second, the Rhine (German Rhein, French Rhin, Dutch Rijn, Romansch: Rein, Italian: Reno) is one of the longest and most important rivers in Europe. ...

After World War I, the drifting contact mine was banned, even if it 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 imaginable. It is just an explosive charge and a trigger lying on the seafloor. They have been used against submarines, as submarines sometimes lie on the seafloor to lower their acoustic signature. They are also used to prevent landing crafts 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. They attached the mines to the front end of many of the obstacles seen in photos of the landing. Combatants Allied Powers Nazi Germany Commanders Dwight D. Eisenhower (Supreme Allied Commander) Bernard Montgomery (land) Bertram Ramsay (sea) Trafford Leigh-Mallory (air) Gerd von Rundstedt (OB WEST) Erwin Rommel (Heeresgruppe B) Strength 326,000 (by June 11) Unknown Casualties 53,700 dead, 18,000 missing, 155,000 wounded About 200...

These mines usually weighed 2-50 kg, including 1-40 kg of explosives (TNT or hexatonal).

Remotely controlled mines

Frequently used in combination with coastal artillery and hydrophones, remote controlled (or command detonation) mines can be in place even in peacetime, which is a huge advantage when it comes to blocking important shipping routes to defend harbours. 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 trace their origins to efforts around 1812 by Robert Fulton. The first use was moored mines used in the American Civil War, detonated electrically from shore. These were seen as superior to contact mines because they only deprived the waterway to the enemy. Robert Fulton Robert Fulton (November 14, 1765 â€“ February 24, 1815) was a U.S. engineer and inventor, who was widely and erroneously credited with developing the first steam-powered ship. ... Combatants Union (remaining U.S. states) Confederate States of America Commanders Abraham Lincolnâ€ Ulysses S. Grant Jefferson Davis Robert E. Lee Strength 2,200,000 1,064,000 Casualties KIA: 110,000 Total dead: 360,000 Wounded: 275,200 KIA: 94,000 Total dead: 258,000 Wounded: 137,000+ The...

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 any mine system today. They are deployed everywhere the water is too deep for bottom mines. Using several kinds of instruments to detect if an enemy is nearby, most frequently a combination of acoustic, magnetic and pressure sensors. More exotic solutions also exist, such as optical shadows or electro potential sensors. These are modern mines and frequently cost many times more than contact mines.

Moored mines are effective against most kinds of ships and, being very cheap compared to other anti-ship weapons, can be deployed in large numbers, making them very useful area denial or "channellizing" weapons. A moored mine usually has a lifetime of more than 10 years, some of them almost unlimited. They are limited by the fact they cannot carry unlimited amount of explosives. These mines usually weighed 200 kg (440 lb), including 80 kg (175 lb) of explosives (hexatonal); more than 150 kg (330 lb) is simply a waste of money, as the mine gets too large to handle and the extra explosives do not add much to the mine's effectiveness.

Bottom mines

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

These mines usually weigh 150-1500 kg (330-3300 lb), including 125-1400 kg (275-3090 lb) of explosives (hexatonal).

Unusual mine systems

There have been several specialized mines developed for other purpose and functions 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 harder.

Rocket mine

Originally a Russian invention the rocket mine is a bottom distance mine that fires a homing rocket (not torpedo) upwards towards the target. It is intended to allow a bottom mine to attack surface ships from a greater depth.

Torpedo mine

This is a self-propelled variety, able to lay in wait for a target and pursue it (such as CAPTOR mine), or swim into a harbor inaccessible to the laying ship. A captor mine is an American naval mine. ...

The U.S. Mark 24 "mine", code-named FIDO, was actually an ASW homing torpedo; the mine designation was a fiction to conceal its function. Anti-submarine warfare is a term referring to warfare directed against submarines. ...

Bouquet mine

The bouquet mine is a single anchor attached to several floating mines. It is designed so that when one mine is swept/detonates another takes its place. It is a very sensitive construction and might not always work.

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.

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. In the Second World War, aircraft came into favour for mine laying U-boat is also a nickname for some diesel locomotives built by GE; see List of GE locomotives October 1939. ...

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. 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. A minelayer is a naval ship used for deploying sea mines. ...

Other methods to lay minefields includes:

Converted merchant ships
Airplanes
Submarines
Combat boats
Camouflaged boats
Dropping from the shore
Attack divers

Most mines are automatically activated when in the water, after a safety has been removed, and can both safely and easily be delivered in almost any method imaginable.

Damage

The damage of a mine depends on the distance from the detonation, and is not always less because the detonation is some distance away.

Direct damage

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

Bubble jet effect

If the mine detonates in the water some distance from the ship, the bubble jet effect happens. The explosion creates a "hole" in the water, and due to the difference in pressure, this sphere will collapse from the bottom. This creates the famous "pillar" of water that can go well 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. The structural damage might break the ship apart. The crew in the areas hit by the water pillar are usually killed instantly. Other damage is usually limited.

The 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 roughly shaken, and everything, bolted down or not, is tossed around. Engines rip free from their beds, cables from their holders, etc. A badly shaken ship usually sinks quickly, with hundreds, or 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. One of the most common wounds is broken femur, close to the hip. The reason for this is the violent upward motion of the ship. To counter this, minesweeper crews are ordered to walk and stand with their knees slightly bent at all times — the "minesweeper walk".

Countermeasures

Weapons are frequently a few steps ahead of countermeasures and mines are no exception. Currently, with modern mine hunting, countermeasures are beginning to catch up (including the use of military dolphins to detect and flag mines). However, the next generation of rocket mines may very well change that. The United States and Russian militaries train and employ dolphins for several reasons. ...

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 have to work inside minefields. These ships are built out of glass fibre or even wood instead of steel to avoid magnetic signatures, they use special propulsion, such as Voith-Schneider propellers, to limit the acoustic signatures and they are made with hulls that produce a low-pressure signature. Of course, these measures create other problems. The ships are expensive, slow and vulnerable to enemy fire. Therefore, they need protection. Many modern ships have a mine warning sonar — simple sonar looking forward and warning the crew if it spots something that might be a mine in the water before the ship. It is only effective when moving slowly. The Voith-Schneider propeller is a specialized marine propulsion system. ... The F70 type frigates (here, La Motte-Picquet) are fitted with VDS (Variable Depth Sonar) type DUBV43 or DUBV43C tugged sonars SONAR (SOund Navigation And Ranging) â€” or sonar â€” (British ASDIC) is a technique that uses sound propagation under water to navigate or to detect other vessels. ...

A ship can be degaussed (more correctly, deoerstedted) using a special degaussing station that contains many large coils and induces a magnetic field in the hull with alternating current. This is a rather problematic solution however, as the magnetic compasses need recalibration afterwards and everything made of metal has to be kept in exactly the same place. Ships slowly regain their magnetic field as they adjust to the Earth's magnetic field, so the process has to be repeated every six months. Degaussing is the process of reducing or eliminating an unwanted magnetic field. ...

A variation on this technique, called "wiping", was developed by Dr. Charles F. Goodeve, RCNVR, which saved precious time and resources. To meet Wikipedias quality standards and appeal to a wider international audience, this article may require cleanup. ... Charles Frederick Goodeve (21 February 1904 â€“ 7 April 1980) was a Canadian chemist and pioneer in operations research. ... The Royal Canadian Navy Volunteer Reserve (RCNVR) was created in 1923. ...

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

Active countermeasures

The active countermeasures are the ways to clear a path through a minefield (or to 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 simple metal wire dragged through the water by one or two ships to cut the mooring wire of floating mines, or a distance sweep that tries to mimic a ship to get the mines to detonate. The sweeps are dragged by minesweepers, either military ships or converted trawlers. Each run covers between one and two hundred meters, and the ships have to move slowly in a straight line, which makes them very vulnerable to enemy fire. This was most famously 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 the minefields. USS Pivot (AM 276) World War II United States Admirable Class Minesweeper shown in the Gulf of Mexico on sea trials 12 July 1944 Image:Hameln Class. ... Categories: Water-transport stubs | Ship types ... Combatants United Kingdom France India Australia New Zealand Newfoundland Ottoman Empire Commanders Sir Ian Hamilton Otto Liman von Sanders Strength 5 divisions (initial) 14 divisions (final) 6 divisions (initial) 14 divisions (final) Casualties 252,000 (205,000 British, 47,000 French) dead 97,000 wounded 145,000+ sick 253,000... Loading a WW1 British 15 in (381 mm) howitzer A howitzer or hauwitzer is a type of field artillery. ...

If a contact sweep hits a mine, the wire of the sweep (which is made of high quality steel) rubs against the wire mooring the mine until it is cut. Sometimes "cutters", explosive devices to cut the mine's wire, are used to lessen the strain on the sweeping wire. Any mine cut free is recorded and either collected for research or simply shot with the deck cannon.

Minesweepers can protect themselves by using an oropesa or paravane instead of a second minesweeper. 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 been employed to drag minesweeping sleds, as in the 1991 Persian Gulf War. 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 Company. ...

The distance sweep tries to mimic 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. Coastal Command was an organization within the Royal Air Force tasked with protecting the United Kingdom from naval threats. ... The Vickers Wellington was a twin-engine, medium bomber designed in the mid-1930s at Brooklands in Weybridge, Surrey, by Vickers-Armstrongs Chief Designer, R.K. Pierson. ...

Modern distance mines are much more sensitive and much harder to sweep. They often contain anti-sweeping mechanisms such as sensitivity only to the noise of certain types of ship or will detonate only after their mechanism has been triggered a specified number of times. They may also only arm themselves (or disarm automatically - known as self-sterilization) after a set time.

Mine hunting

Pinguin B3 mine hunting drone, such are operated from Frankenthal class mine hunters

Mine hunting is very different from sweeping, even if some minehunters can do both tasks. When mine hunting, the mines are located using sonar, then inspected and destroyed either by divers or ROVs (remote controlled unmanned mini submarines). 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. Image File history File links Download high resolution version (1280x960, 936 KB) Summary A Pinguin B3 mine hunting drone (ROV), used to inspect and destroy naval mines. ... Image File history File links Download high resolution version (1280x960, 936 KB) Summary A Pinguin B3 mine hunting drone (ROV), used to inspect and destroy naval mines. ... M1064 GrÃ¶mitz The Type 332 Frankenthal class mine hunter is a 12-ship class of German mine hunters. ... Minehunters are mine-countermeasure ships that detects and destroys individual naval mines. ... It has been suggested that Remote control vehicle be merged into this article or section. ...

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. Mine-clearance dolphins were deployed to the Persian Gulf during the Iraq War in 2003. 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.^[1] Binomial name Tursiops truncatus Montagu, 1821 Bottlenose Dolphin range (in blue) The Bottlenose Dolphin (Tursiops truncatus) is the most common and well-known dolphin species. ... The U.S. Navy Marine Mammal Program (NMMP) is a program administered by the U.S. Navy which studies the military use of marine mammals â€” principally Bottlenose Dolphins and California Sea Lions â€” and trains animals to perform tasks such as ship and harbour protection, mine detection and clearance, and equipment... Map of the Persian Gulf. ... Combatants Republic of Iraq (Saddam Hussein regime), Baath Loyalists, Iraqi insurgency United States, United Kingdom, Coalition of the Willing, New Iraqi Army For other uses, see Iraq war (disambiguation) The Iraq War (2003-present) is an ongoing conflict in Iraq[1], which began with the 2003 invasion of Iraq... This article is about an antipersonnel trap designed for use against humans. ... Cranes at Umm Qasr await cargo. ...

Mine breaking

A more drastic method is simply to take a cargo ship, load it with cargo that makes her less vulnerable to sinking (wood for example) and drive her through the minefield, letting the ship that should be protected follow the same path. Alternatively, a shallow-draught vessel can be steamed through the minefield at high speed in an attempt to generate a pressure wave sufficient to trigger the mines, with the minesweeper moving fast enough to be sufficiently clear of the pressure wave that triggered mines do not destroy the ship itself. These techniques have been used several times during war, not always successfully. They are the only way to sweep pressure mines and modern doctrines calls for such weapons to be hunted rather than swept.

Seehund ROVs used for minesweeping/breaking

An updated form of mine breaking is the use of small unmanned ROVs that can simulate the acoustic and magnetic signatures of larger ships and are built to survive the effects of exploding mines. Image File history File linksMetadata Download high resolution version (2592x1944, 761 KB) Summary Three Seehunde (HohlstÃ¤be) mine sweeping ROVs of the Troika system. ... Image File history File linksMetadata Download high resolution version (2592x1944, 761 KB) Summary Three Seehunde (HohlstÃ¤be) mine sweeping ROVs of the Troika system. ... M1093 Auerbach/Oberpfalz The five ships of the Type 352 Ensdorf class are former Type 343 Hameln class minesweepers that have been upgraded with the TROIKA PLUS system. ... It has been suggested that Remote control vehicle be merged into this article or section. ...

Strategy

Mines are used in many different ways and for different reasons. International law requires nations to declare when they mine an area. This is to make it easier for civil shipping to avoid the mines. The warnings do not have to be specific however. For example, Britain declared areas such as the English Channel, North Sea and French coast mined during the Second World War.

There are three main uses of mines: Offensive, Defensive and Psychological. Offensive mines are placed in enemy waters, outside harbours and in important routes. Their targets are both civilian and military ships, and they are used as much to sink ships as to stop the important sea transports. Defensive minefields protect a coast from enemy ships and submarines, and force them into areas that are easier to defend. Psychological minefields are usually placed in trade routes, and are used to stop shipping to the enemy nation. They are also spread out thinly, to create a feeling of random minefields in large areas. A single mine in a route can stop shipping for days until the entire area is swept.

Minefields can be placed by traditional minelayers, large ships carrying thousands of mines, smaller coastal ships, submarines, airplanes and even by just dropping them into a harbour by hand.

Economy

Just like mine warfare on land the economical burden in mine warfare at sea is very uneven. The cost of producing and laying a mine is usually between 1/10th and 1/200th of the cost to remove said mine. The time aspects are also critical, as it can take up to 200 times the time to clear a minefield than to lay it. Using different methods to make clearing harder can increase this time. Even today parts of minefields left since the Second World War remain, as they are simply too spread out and expensive to clear. Also many of these mines are no longer active, even if contact mines theoretically can be active for hundreds of years.

A simple contact mine can cost as little as $200, a simple influence type around $300. This makes them very attractive weapons in uneven conflicts, as they can deny access for expensive ships to large areas for a long time, without risking friendly losses.

National experiences

U.S. Losses

Since World War II, mines have damaged or sunk 14 U.S. Navy ships, while air and missile attacks have damaged only four. Combatants Allies: Poland, British Commonwealth, France/Free France, Soviet Union, United States, China, and others Axis Powers: Germany, Italy, Japan, and others Casualties Military dead: 17 million Civilian dead: 33 million Total dead: 50 million Military dead: 8 million Civilian dead: 4 million Total dead: 12 million World War II... The United States Navy (USN) is the branch of the United States armed forces responsible for conducting naval operations around the globe. ...

During the Korean War, mines laid by North Korean forces damaged 11 U.S. naval vessels. Combatants Western Allied/UN combatants: South Korea, United States Communist combatants: North Korea, Peoples Republic of China Strength Note: All figures may vary according to source. ...

During the Iran-Iraq War from 1980 to 1988, the belligerents mined several areas of the Persian Gulf and nearby waters. 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. Combatants Iran Iraq Casualties Est. ... Map of the Persian Gulf. ... April 14 is the 104th day of the year in the Gregorian calendar (105th in leap years). ... 1988 (MCMLXXXVIII) was a leap year starting on Friday of the Gregorian calendar. ... --> USS (FFG-58) is one of the final vessels in the United States Navys Oliver Hazard Perry class of guided missile frigates. ...

During the Gulf War, Iraqi naval mines severely damaged USS Princeton (CG-59) and USS Tripoli (LPH-10). Combatants U.S.-led coalition Iraq Commanders George H. W. Bush, Norman Schwarzkopf, Colin Powell Saddam Hussein, Ali Hassan Al-Majid, Hussein Kamel Strength 660,000 ~545,000 Casualties 345 dead, 1,000 wounded 25,000 - 100,000 dead, 100,000 - 300,000 wounded The 1991 Gulf War (also Persian... Categories: Military stubs | Ticonderoga class cruisers ... The second USS Tripoli (LPH-10), an Iwo Jima class amphibious assault ship, was laid down on 15 June 1964 at Pascagoula, Mississippi, by the Ingalls Ship building Corporation; launched on 31 July 1965; sponsored by Mrs. ...

US Mines

The United States Navy MK56 ASW mine (the oldest still in use by the US) was developed in 1966. Since that time, more advances in technology have given way to the development of the MK60 CAPTOR (short for "encapsulated torpedo"), the MK62 and MK63 Quickstrike and the MK67 SLMM (Submarine Launched Mobile Mine). Most mines in the USN's arsenal today are delivered by aircraft to target. The United States Navy (USN) is the branch of the United States armed forces responsible for conducting naval operations around the globe. ... Motto: E pluribus unum (1789 to 1956) (Latin: Out of Many, One) In God We Trust (1956 to present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at federal level; English de facto Government â€¢ President â€¢ Vice President Federal Republic George... A captor mine is an American naval mine. ... The United States Navy (USN) is the branch of the United States armed forces responsible for naval operations. ...

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 MK37 torpedo.

General Characteristics

Type: Submarine laid bottom mine
Detection System: Magnetic/seismic or 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 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) mine. Other Quickstrike versions (MK62, MK63, and MK64) are converted 500 lb (230 kg) and 1000 lb (450 kg) general-purpose bombs.

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

MK60 CAPTOR

The CAPTOR is the United States Navy's primary anti-submarine mine. This deep-water mine is laid by aircraft or submarine, and is anchored to the ocean floor. Upon detection of a hostile submarine, the CAPTOR launches a MK46 Mod 4 torpedo.

General Characteristics

Type: Aircraft, ship or submarine laid magnetically moored mine
Detection System: Reliable acoustic path (RAP) sound propagation
Dimensions:
- Aircraft or Ship laid: 530 mm by 3.68 m (21 by 145 in)
- Submarine laid: 530 mm by 3.35 m (21 by 132 in)
Depth Range: Deep water
Weight:
- Air or Ship laid: 1077 kg (2370 lb)
- Submarine laid: 935 kg (2056 lb)
Explosives: 44 kg (96 lb) of PBXN-103 high explosive in a MK46 torpedo
Date Deployed: 1979

A torpedo in Rail terminology refers to a small explosive device strapped to the top of the rail to alert an approaching train of immediate danger ahead. ...

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

Notes

^ Uncle Sam's Dolphins. Smithsonian Magazine article about the U.S. Navy Marine Mammal Program's mine-clearance work in Iraq.

Smithsonian is a monthly magazine published by the Smithsonian Institution of the United States in Washington, DC External link Smithsonian webpage Categories: Smithsonian Institution | United States magazines | Stub ... The U.S. Navy Marine Mammal Program (NMMP) is a program administered by the U.S. Navy which studies the military use of marine mammals â€” principally Bottlenose Dolphins and California Sea Lions â€” and trains animals to perform tasks such as ship and harbour protection, mine detection and clearance, and equipment...

Contents

Early history