A British troop ship torpedoed in the First World War with a Titanic survivor on board has been discovered in the Aegean Sea.

Built as an ocean liner, the SS Arcadian was chartered by the Royal Navy in 1915 and sunk on April 15, 1917, with the loss of 279 lives.

It was five years to the day after the Titanic sank, and one of the survivors, Thomas Threlfall, would survive the sinking of the Arcadian too.

Now her wreck has been found over a century later, discovered by a Greek team at a depth of 163 metres, southeast of the Cycladic island of Sifnos.

Team leader Kostas Thoctarides said: ‘The main feeling was excitement and a sense of satisfaction. For a long time we have been reading this thrilling story that has so many fascinating aspects.

‘Then we saw the image of her on the seabed, something the human eye is seeing for the first time. 

‘For us it was a journey into the past and the history of the Arcadian, which is unknown to most people in Greece.’

The Arcadian was sunk en-route from Salonika in Greece – now Thessaloniki – to Alexandria in Egypt.

She’d headed west into the Cyclades in the hope of avoiding a German U-boat, detected at the island of Ikaria – but she was unsuccessful.

Those on board had just completed an abandon ship drill when, at 5.44pm, the torpedo hit.

Fired by the UC-74, it struck Arcadian on her starboard side, between the bridge and the foremast.

With most of the crew still on deck from the drill, captain Charles L Willats had the lifeboats launched, and ordered the ship be abandoned – this time for real.

Just five minutes after the explosion, Arcadian’s bow slipped below the water, with her stern lifting out of the sea.

Her escort, HMS Sentinel, led the rescue, with French warships from Milos joining the effort some two-and-a-half hours later.

In all, 1,058 people were saved, and 279 lost – comprising 34 crew, ten members of the navy, and two civilians, with the rest from the army.

Mr Threlfall later said: ‘It was the same day and in the same month that the Titanic went down, and I have come safely out of both affairs.’

He continued: ‘The Titanic stopped afloat for a couple of hours and we had time to turn around, but of course you could not live in the water that night.

‘This time we had calm sea and warm weather, and you had a chance, but with the Titanic you died in the water almost as soon as you got in.’

A statement from Planet Blue, Mr Thoctarides’ company, said the Arcadian was in ‘excellent condition’ and was ‘one of the most impressive wrecks in Greece’. 

It continued: ‘Time seems to have stopped at its sinking in 1917.’

It’s also upright in the water, apparently because its bow hit the seabed while the stern was still sinking.

The hole caused by the torpedo is visible even now.

For Mr Thoctarides it’s the culmination of a decades-long effort. He said: ‘Our historical research on Arcadian started over 20 years ago by collecting information mainly from the British and German archives.

‘Since the year 2000 we have been collecting data on the subject. As the wreck is located in a quite offshore area and a long journey is required to get there, we wanted to be as prepared as possible for these surveys.

‘So we created quite a large file on Arcadian and when we had the opportunity to be in the area for underwater works we located it relatively quickly using sonar.’

No remains or personal artifacts were found on the ship, which was explored externally using an ROV (remotely operated vehicle).

Mr Thoctarides dedicated the discovery to those who perished on the Arcadian.

The ship was built in 1899 by the Vickers, Sons & Maxim company at their yard in Barrow-in- Furness, England.

Built for the Pacific Steam Navigation Company, she was initially named the Ortona, but was renamed the Arcadian after being acquired by the Royal Mail Steam Packet Company in 1906.

Her foe, the UC-74, was built in 1916 at the Vulcan Shipyard in Hamburg, and sank a total of 37 ships during her career.

She was interned at Barcelona in 1918 after running out of fuel, surrendered to France in 1919, and broken up in Toulon two years later.