MAS (motorboat)

A significant success came in December 1917, when an MAS boat managed to sink the pre-dreadnought battleship SMS Wien in Trieste harbor.

The greatest success of Italian MAS was the sinking of the Austro-Hungarian battleship SMS Szent István off Pula on 10 June 1918 by a boat commanded by Luigi Rizzo.

The main Austrian fleet remained securely at anchor in the harbour at Pola (now Pula in Croatia), protected by several layers of defensive booms, impassable to conventional MAS boats.

[2] The craft featured a pair of spiked continuous tracks, intended to allow them to clamber over the booms which were supported by large timber baulks.

The standard engine in World War II was the ASM 184, a 18-cylinder machine capable of producing 1,500 hp (1,100 kW) with 2,000 rpm.

[8] On 1 December 1941, two Italian MAS boats engaged with torpedoes and machine gun fire the Soviet icebreaker Anastas Mykoyan, en route from the Dardanelles to Suez, forcing it to run aground on the Turkish coast off Kastelorizo.

[9] Also in the Aegean Sea, on 27 April 1942, near Kastelorizo, a flotilla of MAS rescued a motor sailing boat with Jewish refugees from Romania.

[12] MAS 554, 554 and 557 sank three allied freighters on the night of 13 August 1942 off Cape Bon, in the course of Operation Pedestal, for a total tonnage of 48,500 tons.

[13] On 29 August 1942, a smaller type of MAS boat, the MTSM, torpedoed the British destroyer Eridge off El Daba, Egypt, disabling it for the remainder of the war.

[14] A flotilla of MAS served at German request as reinforcements in the Black Sea for the planned attack on Sevastopol in June 1942.

In the early hours of 3 August 1942, three MAS boats torpedoed and disabled the Soviet cruiser Molotov south-west of Kerch.

[19] The obsolescence of small MAS became apparent during the conflict, and they were increasingly replaced by larger Yugoslavian E-boats built in Germany and by new improved versions, classified "MS" (Moto Siluranti) by the Regia Marina.