The Syöksy-class motor torpedo boats (), also known as Nuoli-class motor torpedo boats (), were four motor torpedo boats operated by the Finnish Navy. The vessels were 55-foot coastal motor boats (CMBs) designed by Thornycroft, and were built at the Thornycroft shipyard in Woolston, UK in 1928 (MTVà4 and MTVà5), and later at the Turku shipyard in Turku (MTVà6) and the BorgÃÂ¥ shipyard in Porvoo (MTVà7), Finland.
The vessels saw service in World WarÃÂ II. The 55-foot CMBs designed by Thornycroft were released their torpedoes by dropping them from rails in the aft. The boat then had to steer away from the torpedoes path, a manoeuvre that could be quite tricky in the close waters of the Gulf of Finland.
In 1942, the vessels received individual identification symbols on their superstructures. Nuoli had the ace of hearts, Vinha the ace of clubs, Syöksy the ace of diamonds, and Raju the ace of spades.
On July 6, 1941, Syöksy and Vinha sortied to intercept a convoy of three sailing ships headed for Hanko. In heavy seas the torpedoes did not function reliably and the boats could not hit their targets. Instead Syöksy dashed past the lead ship and dropped its depth charges in front of it which exploded and sank the sailing ship. Both Finnish motor torpedo boats escaped unharmed before escorting Soviet ships could respond. It was probably the motor schooner Laama, which was sunk near Tallinn on July 8, 1941, according to Soviet sources.
On the night of July 19âÂÂ20, 1941, Finnish motor torpedo boats were patrolling off the coast of Estonia when a Soviet destroyer (aàminesweeper, according to Soviet sources) opened fire on them. Vinha was damaged and unable to move but Finns were able to tow it to safety while Syöksy made repeated torpedo runs towards the destroyer drawing its fire and distracting it.
On September 1, 1941, Syöksy and Vinha were patrolling south of the Beryozovye Islands when they came across a pair of Soviet freighters. Syöksy torpedoed and sank the lead merchant ( ).
On September 22, 1941, Syöksy sank the Soviet minesweeper (exâÂÂ, an -class tug commissioned into naval service) east of Gogland while it was patrolling near the island with Vinha.
On the night of October 1âÂÂ2, 1941, NuoliâÂÂtogether with âÂÂparticipated in an attack on Soviet naval ships off Gogland. According to some Finnish sources, it was a torpedo from Sisu that sank a . According to other sources, Nuoli and Sisu allegedly sank two Soviet minesweepers as a result of this attack. In reality, according to Soviet sources, Nuoli and Sisu made an abortive attack on the anchored in the bay of Gogland Island at the time.
Syöksy, Vinha, and , as well as a minelaying KM-boat (, or ) participated in the attack on the harbour of Lavansaari on November 18, 1942. Syöksy managed to torpedo the (1,760 tonnes), which sank.