If the sunken sub is the H11 then it will look very similar to this British H28 - there will be another dive to take photos of the wreck site

Divers from Scotland and north-east England have discovered what they think is a World War One British submarine off the east coast of Scotland.

On July 8 2006, members of Edinburgh’s South Queensferry Sub Aqua Club (SQSAC) and Bishop Auckland Sub Aqua Club in County Durham were on a dive looking for an obstruction that had trapped fishing nets in the past and were expecting to find a sunken trawler.

“It was on a trip about a month ago - we were diving on what they call a fisherman’s ‘snag’ on what we thought was a sunken trawler,” explained Stevie Adams, SQSAC Diving Officer.

“It was quite deep – nearly 60 metres - and we were expecting to find a trawler but it was only when we came back that some of the guys thought it looked like a submarine.”

The divers were about three miles off Eyemouth, a small fishing port just north of the English border, when they found the submarine. A further dive on the site was planned to investigate further and this time visibility was much better.

“We could see the conning tower, the hydroplanes, the hatches were there and the bellows,” said Stevie. “We have done a couple of dives since and have got a few more planned.”

The wreck, which is about 45 metres long and 5 metres tall is lying on its port (left) side and is still in very good condition for its age.

The conning tower of the wreck is clearly visible along with the hydroplanes, hatches and the bellows

Stevie started investigating the identity of the sunken submarine with the help of the Royal Navy Submarine Museum in Gosport and now thinks that it is the wreck of British submarine H11. Although several German U-boat wrecks have been found around the coastline fewer British submarines have been discovered.

British Submarine H11 was being towed in 1920 to be scrapped and as far as naval records go, said Stevie, it was assumed that it reached its final destination.

Coast guard records suggest otherwise and point to the fact that H11 in fact sunk off the Scottish coast around the point of the wreck’s discovery. In addition, very few subs from that era were of the same length as the one found.

“We’re 99% certain that it’s this submarine,” said Stevie.

The next dives are planned for August 20 and 23 so more can be found out about the wreck. Underwater photographs will be taken and a video camera may be taken down as well.

60 metres is a deep dive, explained Stevie, and with strong currents in the area careful planning is needed. The divers use mixed gases and ‘rebreathing’ equipment that recycles their exhaled air to give them a longer dive but requires specialist training to use.

Submarine H11 was built in America in 1915 and released to the British Navy in 1917 when the US joined the First World War. It had a crew of three officers and 19 ratings and was armed with torpedoes.