The fourth ship of the class, Gagara (Гагара, Russian for Loon), was built at the Neva shipyard in Saint Petersburg and carried the construction number 102.

However, tensions were still running high and soon after the declaration of independence the Finnish Civil War erupted.

However, only the largest ships managed to return to Russia, due to the harsh ice conditions of the Gulf of Finland.

On April 13, Prozorlivy was conquered by the whites and she was transferred to the Finnish navy, along with her five sister ships (Ryany (later S1), Poslishny (S3), Rezvy (S4), Podvizhny (S5) and No 212 (S6)).

It was also planned that Prozorlivy would have been handed over, but the ageing ship was sold to Finland, where she was included in the Finnish navy.

The plan was to visit all the coastal cities up to Tornio and the group began the journey from Uusikaupunki to Vaasa on 3 October 1925.

They traveled in line formation with one kabellängd (1/10 nautical mile (0.19 km; 0.12 mi)) internal distance and at a speed of 12 knots (22 km/h; 14 mph).

Initially everything went as planned, but as the journey progressed, the wind started to pick up and later developed into a fierce storm, which created difficulties for the ships.

Klas Horn, which was the lead ship of the formation, turned against the wind and headed towards the Swedish coast, followed by Hämeenmaa.

In the middle of the night, the wind speed reached hurricane force 48–55 m/s (173 to 198 kilometres per hour (107 to 123 mph; 93 to 107 kn)), 12 on the Beaufort scale.

[2] The stormy sea created big problems for the torpedo boats when their propellers were lifted too close to the surface.

This reduced their efficiency and what worsened the situation was the fact that the S2's bearings were worn out, which caused a lot of vibrations in the ship and threatened to open up a leak where the shaft went through the hull.

The coal was also slowly running out since the crew had to feed more into the boilers than usual due to the high seas.

The pilot station at Reposaari observed the struggle of the ship in the waters between Outoori and the Säppi Lighthouse.

At the place of the sinking, the sea bed rises sharply, and creates sharp breakers, especially when the wind is coming from west or northwest.

[3] The ship was found in June 1926 and the Ministry of Defence immediately began planning a salvage operation.

The vessel was transported to the Reposaari harbor in Pori, where it was turned on its keel, emptied on water and initially investigated.

This law resulted in the requisition of the coastal armoured ships Väinämöinen and Ilmarinen, the submarine fleet and the purchase of new torpedo boats in the 1930s.

[4] The 23 bodies that were found inside the ship were buried at the Reposaari burial ground in a joint grave, on 15 August 1926.