Royal Navy's submarine (File photo) Source: PA Wire/Press Association Images

THE CREW OF a UK Royal Navy submarine placed the lives of an Irish Sea fishing trawler in danger when it dragged the boat after snagging its nets.

The submarine dragged fishing vessel the Karen at 7 knots for about 30 seconds on the afternoon of 15 April 2015 but did not realise what had happened until about three hours later.

The Karen is a Danish-made wooden fishing vessel that registered in Northern Ireland.

An investigation by the UK’s Marine Accident Investigation Branch has found that the crew of the submarine did not follow proper guidelines that were developed following previous incidents with fishing boats.

The incident happened when the Karen had reached its intended fishing grounds after sailing from Ardglass in Northern Ireland.

The crew had already landed two catches of the day when the nets were deployed underwater for the third time.

Source: Marine Accident Investigation Branch

The investigation found that, when the collision occurred, Karen’s crew heard an unusual noise and realised something was wrong as the trawl warps had unexpectedly tightened and the vessel started to be dragged backwards.

The incident continued for about 30 seconds during which time the vessel became partly submerged under the pull of the submarine. The crew began preparing a life raft before the warp parted and the vessel was released.

The Karen was significantly damaged by the incident but the engine had not flooded and it was possible to return to Ardglass.

Karen returning to Ardglass after the incident with damage evident on port side. Source: MAIB

In 1990, four crew members died when a Royal Navy submarine sunk the Antares fishing boat of the Scottish coast. A code of practice was induced following that incident but this latest MAIB report concluded that “lessons learnt after the Antares accident have been lost”.

Investigators were also critical of the Royal Navy for ‘not fully engaging’ with the investigation.