Fast attack craft

A fast attack craft (FAC) is a small, fast, agile and offensive warship armed with anti-ship missiles, gun or torpedoes. FACs are usually operated in close proximity to land as they lack both the seakeeping and all-round defensive capabilities to survive in blue water. The size of the vessel also limits the fuel, stores and water supplies. In size they are usually between 50–800 tonnes and can reach speeds of 25–50 knots.

A fast attack craft's main advantage over other warship types is its affordability. Many FACs can be deployed at a relatively low cost, allowing a navy which is at a disadvantage to effectively defend itself against a larger adversary. A small boat, when equipped with the same weapons as its larger counterpart, can pose a serious threat to even the largest of capital ships. Their major disadvantages are poor seagoing qualities, cramped quarters and poor ability to defend themselves against aerial threat.

As early as the mid-19th century, the Jeune École's poussiere navale theory called for a great number of small, agile vessels to break up invading fleets of larger vessels. The idea was first put into action in the 1870s with the steam-powered torpedo boat, which was produced in large numbers by both the Royal Navy and the French Navy. These new vessels proved especially susceptible to rough seas and to have limited utility in scouting due to their short endurance and low bridges. The potential threat was entirely extinguished with the introduction of the Torpedo Boat Destroyer (TBD) in 1893, a larger vessel which evolved into the modern destroyer. It could mount guns capable of destroying the torpedo boat before it was within range to use its own weapons.

The idea was revived shortly before World War I with the craft using new gasoline engines. Italy and Great Britain were at the forefront of this design, with the Coastal Motor Boat (CMB) and the Motobarca Armata Silurante (MAS) (Italian: "Torpedo Armed Motorboat"). The outstanding achievement of the class was the sinking of the Austro-Hungarian battleship SMS Szent István by MAS. 15 on June 10, 1918. The equivalent achievement for the CMBs was a lesser success; during the Russian Civil War CMBs attacked the Red Fleet at anchor at Kronstadt on 18 June 1919, sinking the cruiser Pamiat Azova for the loss of four craft.

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