The story of HMS A7 is not well known, so the project aims to raise awareness – locally and nationally – about her life, her loss and contribution to World War 1.

Peter Holt, Promare

The wreck lies with her stern embedded in clay on the seabed about 135ft down. The boat was found in the early 1980s and is a designated war grave – no-one can dive on her without permission from the MOD.

The divers will not enter the wreck, but they will photograph and record every aspect of it, measure the thickness of the hull plates and carry out a full survey of the site.

What they find will help experts from the University of Birmingham create a virtual reality HMS A7 and her wreck site.

The unique 3D model of the boat will be used in a series of public talks and displays in museums to tell the story of A7, early submariners and how they helped pave the way for operations in the Great War.

“The story of HMS A7 is not well known, so the project aims to raise awareness – locally and nationally – about her life, her loss and contribution to World War 1,” said Promare’s Peter Holt.

“The reason why the A7 sank has never been confirmed, so the project will also investigate the possible cause of loss.”

HMS A7 was one of 13 A-class boats built in the first decade of the 20th Century, three of which were lost during training.

HMS A7, commanded by Lt Gilbert Welman, was making a simulated attack on the tender HMS Pigmy on the morning of January 16 1914. 

However, after diving, nothing more was seen of the boat. Sailors on the Pigmy saw bubbles on the surface, suggesting that the submarine was attempting to blow water from her ballast tanks in an attempt to rise.

The location was marked with a buoy before the Pigmy returned to Devonport to report the incident.

Unfortunately, there was only enough air in the submarine for six hours and, tragically, all 11 crew members perished.

Despite numerous salvage attempts over the following month, the A7 refused to move and so it was decided the leave her where she lay.

You can learn more about the plans for the boat at www.promare.co.uk/a7project, where updates on the survey will be posted in due course.