The wreck of a British naval submarine lost for more than 90 years has been found in the Baltic Sea off the coast of Estonia.
HMS E18 - with its complement of three officers and 28 ratings - went out on patrol in May 1916 and was never seen again.
The submarine was one of a handful sent to the Baltic during World War I by Winston Churchill, the First Lord of the Admiralty, to disrupt German shipments of iron ore from Sweden and support the Russian navy.
E18 left its base in the Russian port of Reval - now Tallinn, the capital of Estonia - on the evening of 25 May 1916 and headed west.
The following day she was reported to have engaged and torpedoed a German ship.
A few days later, possibly 2 June, she is believed to have struck a German mine and sunk with all hands.
Following the submarine's loss, Tsar Nicholas of Russia gave posthumous medals to the crew, including my great-uncle, Luke Landale, the 1st Lieutenant, who was awarded the Order of St Vladimir. He was just 27 years old.
The submarine was found last weekend close to the Estonian island of Hiiumaa by a Swedish marine survey company, MMT.
Luke Landale, right, and crew were given posthumous medals
They were guided by information provided by an Australian descendant of one of the crew, Darren Brown - an airline engineer from Melbourne - who has spent years researching the submarine's history.
His great-grandfather, Signalman Albert Robinson survived the loss of E18 because he fell ill with appendicitis shortly before its last patrol and was confined to his bed.
The Swedish survey vessel, the MV Triad, deployed a remote-operated vehicle and obtained the first pictures showing the 181ft (55m)-long submarine in remarkably good condition.
The Baltic water is cold, brackish and anoxic which means wrecks suffer less rust and degradation than in other seas.
There are also fewer potentially damaging ocean currents.
Photographs from the seabed show the submarine with its hatch open, suggesting that it was sailing on the surface when it hit the mine.
David Hill, an expert in E-class submarines who has examined the images, said: "Without a shadow of doubt they do show an E-class submarine and certain details indicate that it is probably E18."
The owner of the survey company, Carl Douglas, said the discovery was the fruition of almost a decade of work.
"We will now complete our mission to document this wreck and inform the relevant authorities," he said.
"We want to investigate the exact cause of the sinking - and to honour the fallen by telling their story."
The E-class boats were considered to be Britain's most successful submarines during World War I.
E18's sister ship, E19, once sank four German transport ships on one day in October 1915.
These were the submarines that flew the Jolly Roger after successful combat operations to cock a snook at the snobbish, surface-based admirals who looked down on their submerged colleagues.
Such was the success of the eight submarines in the Baltic that it was here the Germans developed the convoy system to protect their shipping.
Submarine's wartime wreckage found
E18 carried five torpedo tubes and a 12lb gun on deck. It had a top surface speed of 15 knots, submerged it could make 10 knots.
With its four diesel and electric engines and its twin screws, it had a surface range of about 3,000 nautical miles; submerged it could cover more than 60 nautical miles.
But the Baltic was a dangerous place for submarines. Not only is its entrance between Denmark and Sweden extremely narrow, but the sea itself is shallow, providing few deep hiding places.
Rarely did E18 reach its diving limits of about 200 ft.
E18 was the only E-class submarine lost on active service in the Baltic; the rest were scuttled by the Navy off Helsinki in April 1918 to avoid capture by advancing German forces.
Of the 57 E-class submarines that were built during World War I, 26 were lost.
Conditions on board the E-class submarines were pretty basic and extremely cramped.
There was just one bunk which the three officers shared; the ratings slept where they could.
The heads - or toilets - were more often than not a bucket. The weather in the Baltic was also extremely cold, with much of the submarine's superstructure freezing over the moment it surfaced.
E18, which was launched in early 1915, was once bombed by a Zeppelin airship after its captain, Lt Cdr Robert Halahan, surfaced so he could go to the loo on deck rather than in the cramped conditions down below.
As such, he was literally caught with his pants down.
Shortly before E18's last patrol, Lt Cdr Halahan was told by a fortune teller that his life was "in grave danger".
So he asked the local Vice-Consul's wife if she could inform his own wife of his death - if E18 was lost - before the official Admiralty telegram reached his home.
The story of E18's ill-fated voyage is to be retold in a documentary, Churchill's Lost Submarine, made by Mallinson Sadler Productions and Deep Sea Productions.
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