Aminelayer is anywarship,submarine,military aircraft orland vehicle deployingexplosive mines. SinceWorld War I the term "minelayer" refers specifically to a naval ship used for deployingnaval mines.^[1] "Mine planting" was the term for installingcontrolled mines at predetermined positions in connection with coastal fortifications or harbor approaches that would be detonated by shore control when a ship was fixed as being within the mine's effective range.^[2][3]

An army's special-purposecombat engineering vehicles used to laylandmines are sometimes called "minelayers".

Before World War I, mine ships were termedmine planters generally. For example, in an address to theUnited States Navy ships of Mine Squadron One atPortland, England,Admiral Sims used the term "mine layer" while the introduction speaks of the men assembled from the "mine planters".^[4] During and after that war the term "mine planter" became particularly associated with defensive coastal fortifications. The term "minelayer" was applied to vessels deploying both defensive- and offensive mine barrages and large scale sea mining. "Minelayer" lasted well past the last common use of "mine planter" in the late 1940s.

The most common use of the term "minelayer" is anaval ship used for deployingsea mines.Russian minelayers were highly efficient sinking the Japanese battleshipsHatsuse andYashima in 1904 in theRusso-Japanese War.^[5] In theGallipoli Campaign ofWorld War I, mines laid by theOttoman Empire's Navy'sNusret sankHMS Irresistible,HMS Ocean, and theFrench battleship Bouvet^[6] in theDardanelles on 18 March 1915.^[7]

In World War II, the British employed theAbdiel minelayers both as minelayers and as transports to isolated garrisons, such asMalta andTobruk. Their combination of high speed (up to 40 knots) and carrying capacity was highly valued. The French used the same concept for thecruiserPluton.

A naval minelayer can vary considerably in size, from coastal boats of several hundredtonnes indisplacement todestroyer-like ships of several thousand tonnes displacement. Apart from their loads of sea mines, most would also carry other weapons for self-defense, with some armed well enough to carry out other combat operations besides minelaying, such as the World War II Romanian minelayerAmiral Murgescu, which was successfully employed as a convoy escort due to her armament (2 × 105 mm, 2 × 37 mm, 4 × 20 mm, 2 machine guns, 2 depth charge throwers).

Submarines can also be minelayers. The first submarine to be designed as such was theRussian submarine Krab.USS Argonaut (SM-1) was another such minelaying submarine. Although there are no modern dedicated submarine minelayers, mines sized to be deployed from a submarine's torpedo tubes, such as theStonefish, allow any submarine to be a minelayer.

In modern times, few navies worldwide still possess minelaying vessels. TheUnited States Navy, for example, uses aircraft to lay sea mines instead. Mines themselves have evolved from purely passive to active; for example the USCAPTOR (enCAPsulated TORpedo) that sits as a mine until detecting a target, then launches a torpedo.

A few navies still have dedicated minelayers in commission, including those ofSouth Korea,Poland,Sweden andFinland; countries with long, shallow coastlines where sea mines are most effective. Other navies have plans to create improvised minelayers in times of war, for example by rolling sea-mines into the sea from the vehicle deck through the open aft doors of aRoll-on/roll-off ferry. In 1984, theLibyan Navy was suspected of having mined theRed Sea a fewnautical miles south of the Suez Canal using the Ro-Ro ferryGhat, other nations suspected of having similar wartime plans include Iran and North Korea.

Beginning inWorld War II,military aircraft were used to deliver naval mines by dropping them, attached to aparachute. Germany, Britain and the United States made significant use of aerial minelaying.

Anew type of magnetic mine dropped by a German aircraft in a campaign of mining the Thames Estuary in 1939 landed in a mudflat, where disposal experts determined how it worked, which allowed Britain to fashion appropriatemine countermeasures.

The BritishRoyal Air Force minelaying operations werecodenamed "Gardening". As well as mining the North Sea and approaches to German ports, mines were laid in theDanube River nearBelgrade,Yugoslavia, starting on 8 April 1944, toblock the shipments of petroleum products from the refineries atPloiești, Romania.^[8]

"Gardening" operations by the RAF were also sometimes used to assist incode breaking activities atBletchley Park. Mines would be laid, at Bletchley Park's request, in specific locations. Resulting German radio transmissions were then monitored for clues which could help deciphering messages encoded by the Germans usingEnigma machines.

In thePacific, the US dropped thousands of minesin Japanese home waters, contributing to that country's defeat.

Aerial mining was also used in theKorean andVietnam Wars. In Vietnam, rivers and coastal waters were extensively mined with a modified bomb called adestructor that proved very successful.

Some examples of minelaying vehicles:

• Shielder minelaying system
• Zemledeliye (minelaying system)
• GMZ family of minelayers, which the2S4 Tyulpan is based on, usingTM-62 series mines
• Minenwerfer Skorpion
• Type 94 Minelayer
• Istrice (M113 variant)

• List of minelayer ship classes
• List of mine warfare vessels of the US Navy in the Second World War
• Mine Planter Service (U.S. Army)
• Minesweeper (ship)
• Submarine mines in United States harbor defense

• Hartcup, Guy (1970).The Challenge of War. New York: Taplinger Publishing Company.ISBN 9780800814311.
• Hartmann, Gregory K. (1979).Weapons that Wait: Mine Warfare in the U.S. Navy. Annapolis, MD:Naval Institute Press.ISBN 0-87021-753-4.
• Jurens, W. (2016). "Life in the Slow Lane: Some Thoughts on Minelayer and Netlayer Evolution".Warship International.LIII (1):59–68.ISSN 0043-0374.

• Dewar, Alfred (1922)."Minesweeping and Minelaying" .Encyclopædia Britannica. Vol. 31 (12th ed.). pp. 949–995.