A RED-FACED navigation expert was left high and dry when he sailed his yacht too close to the shore and ran aground on a mudbank.

Captain Peter Mitchell, a former lecturer in marine navigation, was stranded for seven hours and had to be rescued by lifeboat.

Despite his experience, Mr Mitchell set sail in his boat The Hlin without any radio or means of raising the alarm if he got into difficulty.

He came unstuck after managing to navigate himself on to a mudbank on the River Wear, at Sunderland, at about 6.30pm on Tuesday. Both the inshore lifeboat and the all-weather lifeboat from the RNLI went to the scene.

Simon Tait, of HM Coastguard, said: "It's really embarassing for someone who is supposedly a marine navigation expert to run aground on a simple stretch of river like this. He must be so embarrassed.

"This is a part of the river where the mudbanks are especially prominent.

"Any pilot knows not to travel too close to the edge - especially at low tide."

Cpt Mitchell, a former lecturer at South Tyneside College, declined to comment at his home on an exclusive marina development in Sunderland yesterday.

His wife, Elizabeth, said: "It's been rather unpleasant for him and he would prefer just to forget about it."