EML Kalev EML " Kalev " was one of two submarines of the Republic of Estonia launched in 1936 at Vickers and Armstrongs Ltd . in England . Her sister , " Lembit " , survived the Second World War . History . The " Kalev " was the second pre - war Estonian Navy submarine . Estonia is a maritime nation and as every country with a long coastline has to defend and safeguard its territorial waters . With due regard to the experiences of World War I the submarines found their proper application in the pre - Second World War Estonian Navy . The collection organised by the Submarine Fleet Foundation in May 1933 developed into a one of the most successful undertakings among the similar events demonstrating a nation - wide determination to defend one ’ s country . In the course of building and testing two submarines the Estonian crews got a top level naval training of the time in England in 1935 - 1937 . In the period of 1937 - 1940 the submarines " Lembit " and " Kalev " were the most imposing naval vessels of the Estonian Navy . Their non - interference upon annexation of Estonia by the USSR was a political decision made irrespective of the will of the navy . " Kalev " in World War II . The submarine " Kalev " joined the Estonian Navy in spring 1937 where she operated until the Soviet take over in 1940 . ( On 24 February 1940 , The Third Reich had expressed its interest in obtaining the submarine , if Estonia would sell it , but this offer was turned down . ) Service in the Soviet Navy . The submarine was formally taken over by the Soviet Navy on 18 September 1940 , by which only five men of the submarine crew remained in place , to instruct the new Soviet crews . After the outbreak of the German - Russian war in June 1941 , " Kalev " was re - complemented , having a totally Russian - speaking crew , although the original name " Kalev " was retained . During the Second World War the " Kalev " participated in military operations among the vessels of the Soviet Baltic Fleet . " Kalev " did not return from her second patrol and was reported as missing since 29 October 1941 . Possible wreck . " Kalev " ’ s ultimate fate or the location of the wreck was unknown for a long time ( it was usually assumed that she hit a mine and sunk off Keri in the Gulf of Finland between Tallinn and Helsinki , but she could have been anywhere between Kronstadt and Hanko ; some sources suggested she was scuttled in the Tallinn Bay during the Soviet evacuation on 28 August 1941 ) . In June 2010 , an Estonian Maritime Museum research team concentrated their efforts on finding " Kalev " . It was assumed that " Kalev " hit a mine and sunk at a minefield off Cape Juminda . On 30 June 2010 a wreck of a submarine was found five miles north of Cape Juminda , Northern Estonia by the Estonian Maritime Museum research vessel " Mare " . According to marine archeologist Vello Mäss , the specific shape of mine shafts of the submarine seen on the sonar screen indicate a probability of about 95 % that the wreck found is " Kalev " . Further research is needed to confirm the finding . The finding of the research vessel " Mare " suggests the high probability that " Kalev " has been found and she sank as a result of hitting a mine near Cape Juminda . Later it was discovered that despite the wreck looking like a submarine , it turned out to be an old aerostat . The " Kalev " is still missing .