QUOTE (stefanf @ Jul 4 2007, 18:03 )

(Letade, men hittade konstigt nog inget ämne om det här.)
Från
Finnish Navy in World War II:
QUOTE
Continuation War - 1942
It was estimated by Finns and Germans that Soviet submarine arm had still at least 40 boats left. They would most certainly start some operations during the season. Light naval units would also be active. Germany had suggested moving of "Vetehinen" class boats to Polar Sea. Finns considered this unrealistic as the boats had only two weeks operating time. Besides, the Baltic Red Fleet was not finished yet and Finland would need all units it had. During winter the towers of "Vetehinen" class boats had been modified and 20 mm Madsen gun moved from deck to tower.
After the winter Vetehinen and Iku-Turso were ready for operations 16 May. The other boats had overhauls and tests finished in June: Saukko 9.6., Vesikko 10.6. and Vesihiisi 29.6. Overhaul of Vesihiisi was longer as the boats batteries were replaced. As the Italian T/40 torpedoes had been unreliable during the previous year, the boats took in British T/33 torpedoes. Louhi was ordered as tender for the Submarine Flotilla. The new commander of the Flotilla was commander K. Pakkala.
The most succesful operation of the Finnish submarines was against Soviet submarines in Ahvenanmeri in 1942. The Soviet submarine offensive had mixed up the sea transport system and all possible units were concentrated to eliminate enemy submarines. The idea to use submarines against their Soviet counterparts was found in June. At first Vesikko was sent to operate in sea area between Helsinki and Tallinn. This gave no results. In August-September all "Vetehinen" class boats and Vesikko were stationed in Maarianhamina for a very unusual task. The boats were to act as convoy escorts and hunt down their Soviet counterparts. The first proposed tactic was to detect the submerged enemy with hydrophones and then attack with depth charges. During the practices in 11-20 August it was concluded that the best possible method would be totally different. Instead of searching submerged enemy boats, the idea was that by using electric motors and hydrophones it would be possible to surprise enemy submarines on surface loading their batteries. These operations started in September. The Finnish boats would rest by day and hunt by night.
The "Vetehinen" class boats and Vesikko were all equipped with a 12 microphone hydrophone. They were tested first surfaced, but it was found out that waves in 4 Beauforts will lower their performance significantly. It was concluded that when surfaced they were not able to detected submerged enemy submarines, but they could easily detect approaching torpedoes and warn the convoy. When submerged the Finnish boats could detect in cold water merchantship engines from 40-50 nautical miles. The "Vetehinen" class boats were even equipped with four depth charges in a rack on stern. The Finnish boats had their bows painted yellow, in tower was a yellow line and during nights they had a blue-white light showing up. The first depth charge test was done in Vesihiisi 3. August. The boat moved at 10 knots and the depth charge exploded at 45 m depth.
The boats had been operating Ahvenanmeri for almost two months before they succeeded. They had all some contacts but did not got into shooting position. The fuel pump of Vesikko had broken, and after repairs in Helsinki the boat made four patrols there. The large "Vetehinen" class boats remained in Maarianhamina. 21.10.1942 Vesihiisi sank Soviet S 7 at Lågskär by torpedo. Vesihiisi was patrolling in the south part of Ahvenanmeri, about 12 miles SW from Lågskär (59o50´N - 19o50´E). Vesihiisi sailed at course 220o and located the Soviet boat at 8 000 meters distance in south in bearing 190o. The enemy boat was sailing course 320o at 12 knots. The sky was partly clouded, wind was light and sea was calm. The time was 19.26 so it would have been dark, but the moonlight. The enemy boat was first spotted by my grandfather, who was awarded by his commander, lieutenant-commander Olavi Aittola with a packet of cigarettes. The situation was good for the Finnish boat as the northern horizon was dark and southern light due to moonlight. Vesihiisi changed course to 200o and sailed with full 8 knots speed that electric motors gave directly towards the enemy boat. A few minutes later Vesihiisi changed course to 255o. At 19.41 when estimated distance was 2 000 meters one bow torpedo was fired. The commander believed to have missed as no explosion was seen after two minutes and ordered to open fire with 76 mm deck gun. A detonation was seen in the stern of the enemy boat after only one shot. The distance had been close to 3 000 meters. Four men, including commander Sergei Lisin, were taken prisoner. One of the survivors, starshina V. Kunitsa, had no duties at that moment and had therefore asked permission to enter bridge for a smoke just before the torpedo hit. The wreck of S 7 was discovered in July 1998 by a Swedish diving team.
26.-27.10.1942 Finnish merchant ship Betty H. was sunk from convoy by submarine torpedo 26 October. Submarines Vetehinen and Iku-Turso were ordered to hunt. They got a hydrophone contact about 10 miles west from Lågskär and followed enemy boat from 13.27 clock for more than four hours, but then lost the contact. This boat was most likely the Shtsh 307 that escaped.Vetehinen decided to return to Maarianhamina by the Nyhamn way. Iku-Turso also turned home but decided to make a detour to west and sail into the archipelago through Kobbaklintarna way. It was dark and visiblity poor due to drizzle. At 19.40 Iku-Turso turned east to enter the seaway, when suddenly a large enemy submarine was seen closing fast only 100 m away. The enemy boat passed Iku-Turso at 30 m distance and Iku-Turso opened fire with 20 mm Madsen gun. About 50 shots were fired. Some hits were seen in enemy tower, but it disappeared into darkness and drizzle. Iku-Turso got again hydrophone contact and followed it easily. Rain had gone and in moonlight visibility was 4-5 miles. At 23.51 a submarine tower was seen in direction given by hydrophone. The enemy boat surfaced and sailed to east with high speed. At 23.58 Iku-Turso shot two torpedoes against the enemy submarine and the victim, Shtsh 320, sank 00.01 at 20 miles west from Marhällan. The distance had again been estimated too short (this time it was actually 4 200 meters instead the estimated 2 000 meters) and five gunshots were fired before one torpedo hit. Luck was on the Finnish commanders side. Iku-Turso was commanded by lieutenant-commander Eero Pakkala.
5.11.1942 Vetehinen sank Soviet Shtsh 305 at Gisslan by ramming. One of the convoys had located a submarine in Ahvenanmeri and Vetehinen and Iku-Turso were sent after it. The weather was partly clouded, eastwind was light and sea was light. The visibility was poor to southeast - southwest. Vetehinen was in the north part of its patrol area, when at 21.18 it located at bearing 360o a surfaced enemy boat sailing westward. The position was between Gisslan and Simpnäs (60o01´N - 19o11´E). The course was changed towards the enemy that dived after ten minutes. Vetehinen changed its course to 270o. With hydrophone contact was again gained and at 22.50 the enemy boat surfaced less than 1 000 m away. The enemy was now southwest from Vetehinen and sailing approximate course 110o. Vetehinen had to turn towards the enemy to get into a position to shoot the torpedoes. The distance decreased rapidly, speed was lowered and both bow torpedoes shot. The distance was smaller than estimated, only 250 meters, and torpedoes missed probably under the target. Gun fire was opened and with six knots speed Vetehinen charged on the enemy boat. The first 76 mm shell hit enemy tower and commander, lieutenant-commander Antti Leino decided to ram. Vetehinen hit the Shtsh-class boat ahead of the tower and its net cutter cut deeply in enemy pressure hull. Tense seconds followed; will Vetehinen get loose from its victim, or will they sink together. The Finnish boat had some damages, but returned home safely and was docked a week later. The damages included cracked bow, lower net cutter was gone, starboard depth rudder was jammed and bent 10o down, bottom plates bent for first 10-15 meters, side plating bent for 2 m2 area and number six dive tank was leaking.
/Per