MAS (short for Italian words Motoscafo armato silurante ) is the name of a class of Italian torpedo boats, or rather armed boats, from the period of both world wars. The units built in the years 1915-1918 were approx. 16 m long, with a total width of approx. 2.6 m. The drive was usually provided by two Isotta-Fraschini combustion engines with 225 HP each. Weapon configurations varied greatly, but often included two 356mm torpedoes, a 47mm or 75mm cannon, and machine guns.
MAS type units were used extensively in the Italian Regia Marine in 1915-1918. Most often they were created as a result of rebuilding confiscated civil motorboats and adapting them to the requirements of the maritime battlefield. The majority of units of this type were used in the Adriatic Sea against the Austro-Hungarian fleet. On the other hand, the MAS type motorboats achieved their undoubtedly greatest success in December 1917, when they managed to break into the base in Trieste and sink the battleship SMS Wien, and in June 1918, when they sent the Austro-Hungarian dreadnought SMS to the bottom. Szent Istvan. The MAS type motorboats (more precisely: the MAS 500 type) were also used on a large scale in 1940-1945, but then they were boats capable of accelerating up to 45 knots and armed with 450 mm torpedoes and anti-aircraft machine guns. During World War II, MAS boats operated not only in the Mediterranean, but also in the Red and Black Seas, where they fought with the Soviet Black Sea Fleet.
