A MOTHER'S mercy plea for a man who admitted causing her son's death in a river accident failed to stop him being jailed yesterday.

Engineer Sean Robinson, 35, was sentenced to four years following the death of lifelong friend Mark Smith.

Mr Smith, 29, was catapulted into the River Tyne as the inflatable boat that Robinson was piloting hit another boat carrying Sea Cadets as young as 11.

At Newcastle Crown Court, just 150 yards from where the collision happened last August, there were cries from the public gallery as Mr Justice Bennett passed sentence for manslaughter.

Robinson, who has a two-year-old daughter, will appeal against the sentence, his solicitor said afterwards.

The court heard how Robinson regularly took his high speed boat on visits to the pub to flout drink-drive laws - knowing that drinking while in charge of a boat is not outlawed.

The court heard that Robinson, of St Peter's Basin, Newcastle, took his inflatable a few miles along the River Tyne to a pub on the city's quayside.

With him were friends Mr Smith, from Dunston Hill, Gateshead, and Malcolm Harper. At the pub, he drank a pint of lager and at least one bottle of red wine, the court was told.

When Mr Harper was "boisterous", the trio were asked to leave and sped off in the boat at about 28mph, despite the speed limit being 7mph.

He was also on the wrong side of the river.

He failed to see a small boat carrying three Sea Cadets and two adults, which was acting as a safety vessel for other cadets on the river.

The court heard how teenager Fiona Robinson put the boat into reverse, possibly averting a worse accident.

The accident, just upstream from the new Gateshead Millennium Bridge, caused Mr Smith to be thrown into the river. His body was not found until a week later.

Mr Harper, who was thrown on to the other boat, and the defendant were also injured, but the occupants of the other boat were not badly hurt.

Eric Elliott, defending, told the court that Mr Smith's mother, Sheila, had come to rely upon the defendant for support after the accident