Missing sub resurfaces after 90 years.

TALLINN -- A British submarine which was lost in action over 90 years ago in the Baltic sea has just been found. The submarine HMS E18, taking part in an extraordinary naval operation authorized by Winston Churchill at the outbreak of the First World War never returned from a routine patrol in May 1916. As no one witnessed her sinking, no trace was ever found--until now.

The submarine was one of a handful sent to the Baltics during World War I by Churchill, who was First Lord of the Admiralty, to disrupt German shipments of iron ore from Sweden and to support the Russian navy.

HMS E18 left its base in the Russian port of Reval (now Tallinn) on the evening of May 25, 1916 and sailed west. The following day she was reported to have engaged and torpedoed a German ship. A few days later, possibly June 2, she is believed to have struck a German mine, going down with all hands on board.

For the past 10 years, a group led by Swedish historian-explorer Carl Douglas has been researching the operations of the Royal Navy Submarine Squadron that fought in the Baltic in World War I. Having found many of the ships sunk by these submarines, they turned their attention to the one British submarine lost at sea: the HMS E18.

Through a unique collaboration with an Australian descendant, the submarine was finally located. Melbourne-born Darren Brown's great-grandfather was the telegraphist on the ill-fated submarine. Listening to the stories told by his grandmother, he began his investigation into the history of the sub. He became drawn into the fascinating story of bravery and heroics, spending much of his spare time over the years delving into the historical archives of Britain, Germany, Estonia and Russia.

Armed with this information, Swedish survey company MMT sent the MV Triad to a designated search area off the Estonian island of Hiiumaa last week. Using side-scanning technology, the first contact with the submarine was made in an area known to have been mined by Germany during WWI. A remotely operated vehicle (ROV) was then deployed and pictures of the submarine, not seen since 1916, made their way to the surface.

"Without a shadow of a doubt, they show an E-class submarine, and certain details indicate that it is probably the E18," said expert David Hill on examining the first pictures.

The Baltic campaign is a long-forgotten episode of the First World War but, according to naval historian Eric Grove, it was the most successful submarine campaign of the war undertaken by the Royal Navy. Its impact was out of proportion to the number of submarines deployed (in total 5 E-class subs and 3 C-class subs), causing the Germans to completely rethink their strategy in the Baltic. They introduced the convoy system to ensure that vital iron ore supplies from Sweden made it through the Baltic to Germany. The British submarines' main role was to support the Russian Navy's efforts and, since the crews spent much of the war in Russia, they became unwitting witnesses to one of the greatest upheavals in world history: the Bolshevik revolution.

The E18 was the only one of this flotilla of submarines to be lost in action; the others were all scuttled to prevent them falling into the hands of the Germans when the Russian war effort collapsed in 1917. Their crews made it home to Britain but, for the men and officers of HMS E18, their's was a different fate in the cold waters of the sea in May 1916. Thirty-three men were lost, including three Russians serving on board in a liaison capacity. The E18, captained by Lt. Cdr. R. C. Halahan, had its last known sighting on May 28, 1916, returning from a mission where she is reported to have torpedoed the German destroyer V100. Lt. Cdr. Halahan was awarded Russia's highest military honor, the Order of St. George, by Czar Nicholas II, an award never normally awarded posthumously.