A teenager who suffered catastrophic head injuries in a high-speed power boat race staged at Portland Harbour today won a £5.5 million compensation pay-out.

Olympic torch bearer, Ben Ridd, now 23, was struck by the bows of a pursuing "Sorcerer"-type boat in the June 2005 tragedy.

The vessel he was co-piloting "hooked and came to a stop in the water" after rounding a marker buoy, his QC, John Ross, told London's High Court.

The pursuing boat had "nowhere to go" because the harbour course was so busy, claimed the barrister, resulting in the boat going "over the top of his head".

Ben's helmet flew off in the collision which knocked him out cold and catapulted him into the water - from which he was rapidly pulled out and airlifted to Dorchester Hospital.

There was no roll bar fitted on his boat - described as a "ski boat with a low free board" and kitted out with a 25 horse power engine.

And Mr Ross explained there had been some doubt about whether the race should go ahead due to the "choppy" seas.

Ben sustained "the most severe head injuries", said the barrister, leaving him with permanent mobility and cognitive problems.

"They have left him permanently incapacitated," Mr Ross told the court.

Ben, of Herstons Close, Poole, was in court today as Mr Justice Mitting approved a £5.5 settlement to cover the enormous costs of the lifetime's care he will need.

Through his mother, Leanne Ridd, he sued the Royal Yachting Association, which oversees the organisation and safety standards in coastal racing events.

The race in which Mr Ridd came to grief involved "head-to-head racing" between children aged between 13 to 16, with boat speeds hitting over 30 mph.

The collision occurred as a "racing fleet" of nine boats was rounding the first marker buoy which involved a 90 degree turn.

The buoy was positioned 600 metres from the start line and, as a result, the boats were still "bunched together" as the tragedy unfolded, Ben's lawyers claimed.

He "nearly died" in the accident, the court heard, which led to a devastating brain haemhorrage as well as other severe physical injuries.

He was in a coma for three weeks and underwent a gruelling six-month course of rehabilitation before he was allowed home.

The legacy of his accident was brain damage which rendered him paralysed down one side, but he fought back in the years after the accident to relearn some of the basic skills of life.

And in July 2012 a moment of personal triumph came when he became an Olympic torch bearer seven years after the calamity which blighted his life.

He now uses a stick to get around, but can walk for no more than a mile even with support, his lawyers say.

Mr Justice Mitting said he had "no hesitation" in approving the settlement - also giving the family his best wishes for the future.