We are aware that she (the Radiant) went down fast and we have also heard stories about the liferafts

Rear Admiral John Laing

Although he wore a life jacket when the vessel went down it failed to inflate.

Skipper William Lawson and crewmen William Ritchie, Sean Downie, William Beedie and George Maskane, all from the North-east of Scotland, were rescued.

Rear Admiral Laing told BBC Scotland: "Our first priority is to gather all the evidence.

"We are aware that she (the Radiant) went down fast and we have also heard stories about the liferafts.

'Key feature'

"We don't know where our lines of inquiry will take us but both those aspects will be looked at thoroughly."

He said he had not yet received feedback from inspectors who were conducting their investigation.

"The important thing is to find out what really happened so we do not miss a key feature."

Referring to the life jackets Rear Admiral Laing said: "We will be looking at them and if there is a problem then we will identify it and make a recommendation."

The Radiant was a twin rig trawler built by the La Parilla Shipyard in northern Spain and delivered to Peterhead in April 2001.