All 27 crew on board the UC-42 died when the submarine sank while laying mines during the First World War. The vessel is believed to have been accidentally sunk by one of its own mines.
A team of five amateur divers discovered the wreckage on November 6. Found in 27 metres of water just off Roches Point, the U-boat measured about 38 metres long and was found in remarkably good condition with little obvious explosive damage.
It had been believed that divers using explosives from HMS Vernon torpedo school had destroyed the submarine in July 1919, with the remains being dispersed on the seabed by wire sweeps.
One of the divers who made the discovery, Ian Kelleher, said the search for the wreckage was almost a “religion” for keen divers.
“It was a religion in diving terms around here that there was a U-boat missing out there. The fact that it had never been found made it more of a mystery, and we believed that by finding it that maybe we could tell the story of what happened it and its crew, so we set out many years ago actually to look for it. We got lucky and we found it,” he said.
The CIT chemistry student said the dive team had laid a plaque of remembrance near the propellers, which contained the number stamp used to positively identify the vessel.
“Once it sank in September 1917, the British Admiralty dived to confirm that it was there. We believed that if any damage had been done to it by the British, there would still be remains of it there. We just wanted to find it and see what was left of it. What we found, on the other hand, was quite the opposite. It was an intact submarine lying on the bottom and not the scattered remains we had believed we would find down there,” he said.
Mr Kelleher said the team would try to contact the relatives of the crew and urged divers visiting the wreckage to respect the site as a grave.
“There aren’t very many U-boats in Ireland that are within the reach of ordinary divers. This is, possibly, within the reach of most divers out there. I do believe it will be a magnet for divers. I would like to stress that it is a grave, however. We have treated it as such and we have laid a plaque there and anybody that dives it we would ask to look but not touch,” he said.