A speeding driver who left a former bodyguard for the Qatar royal family with brain damage and multiple fractures in an horrific collision has been jailed.

Gary Mockford had accelerated in his Lexus to jump a red light at a busy junction in Leybourne when he struck motorcyclist Tom Bell.

Mr Bell, who had celebrated his 40th birthday just days earlier, was on his way home from his job as head of security at the Westfield shopping centre in Stratford, London.

He took up that role on his return from his close protection job in the Middle East in November 2014, a court heard.

Two years earlier Mr Bell had also worked as venue group security manager for the London Olympic Games.

The collision at 5.15pm on March 16 last year was described by witnesses as sounding 'like an explosion'.

Mr Bell was thrown through the air and landed unconscious several metres away from the point of impact.

His motorbike split in half and debris 'rained down' onto the road, the court heard. The handlebars and front suspension were later found in a nearby field.

As well as his brain injury, Mr Bell suffered punctured lungs and fractures to his ribs, collarbone and nose, as well as ruptured ligaments to his right knee for which he is still awaiting surgery.

While being airlifted to hospital, paramedics had to carry out surgery to his chest and once at London's King's College Hospital, up to 20 doctors battled to save his life.

Mr Bell spent five weeks in their care before being transferred to a stroke unit, described as inappropriate for his medical needs, at Maidstone Hospital, where he then remained for two months.

"He has completely lost his former athletic way of life, his job, his driving licence, and marital intimacy, and a huge burden has been placed on his wife..." - Judge Charles Macdonald QC

He was subsequently moved to a neuro rehabilitation centre in Northampton before finally being allowed home 10 days later.

But Maidstone Crown Court heard he faced 'considerable and ongoing difficulties', resulting in him and his wife Anna having to move from their cottage in Staplehurst, to a modified bungalow near West Malling.

As well as his brain and leg injuries, the one-time competitive marathon runner and Ironman triathlete has been left partially blind.

He has no memory of the accident or preceeding few months of his life, including his birthday party, can no longer work or drive, and has temper outbursts.

In emotionally-charged victim impact statements, Mr Bell detailed the life-changing effects of his disabilities, while his swimming teacher wife wrote of how she had 'lost' her 'articulate, intelligent, hard-working and confident' husband.

Mockford, a Yodel delivery driver, cried in the dock as they were read out.

The court heard the traffic light at the five-carriageway junction between the A20 London Road and the A228 Ashton Way had been red for three seconds when he drove through it.

The Lexus airbag control system later revealed Mockford had accelerated from 42mph to 61mph in the 100 metres prior to hitting Mr Bell. The limit in that area is 40mph.

The car then careered into and demolished another set of lights before hitting a stationary Vauxhall Insignia.

Mockford initially told police at the scene the light was amber when he drove through it and that the motorcyclist 'must have opened his bike up very fast'.

But prosecutor Peter Forbes said Mr Bell, who was at the front of queuing traffic, waited three seconds after his light changed to green before pulling away slowly.

Mockford, of Oakmead, Tonbridge, originally denied causing serious injury by dangerous driving but pleaded guilty on Friday just three days before his trial was due to start.

He was jailed for 25 months and two weeks, and banned from driving for five years and three weeks.

The maximum sentence for such an offence is five years' imprisonment.

Jailing Mockford, Judge Charles Macdonald QC said Mr and Mrs Bells' lives had changed 'beyond recognition' and appropriate punishment could only be met by immediate custody.

"There was nothing to prevent the defendant from obeying the traffic signals. He deliberately chose to speed up and jump the lights, and his final speed was very excessive," he added.

"The harm to Tom Bell and his wife Anna has been very great. It is difficult to summarise in a few words the effect this collision has had on these two individuals and their lives.

"He has completely lost his former athletic way of life, his job, his driving licence, and marital intimacy, and a huge burden has been placed on his wife.

"The neuro injury has had huge complications and he suffered months of traumatic amnesia. He still suffers from mental instability, with continuing memory lapses and a compulsion to explain his condition to others in a stilted way.

"He and his wife have had to move in order to cope with his new way of life. It is no exaggeration to say that two people's lives have been changed beyond recognition by this collision."

The court heard that Mr Bell's amnesia was so severe he even absconded from Maidstone Hospital during his care.

"In my eyes he has been reduced to a child-like state and is having to relearn life..." - wife Anna Bell

He walked up to four miles to the scene of the smash, where he was found 'distressed and disorientated' two hours later.

As a result, Mr Bell was made subject to a deprivation of liberty order and had to be locked in by hospital staff.

In her statement to the court, Mrs Bell spoke of her own frustration and exhaustion, and said she no longer felt like a wife but simply her husband's carer.

She said intimacy between them had been reduced to 'a goodbye kiss or forced hug'.

"It is sad to watch my husband, an articulate, extremely intelligent, hard-working man, go through this," wrote Mrs Bell.

"In my eyes he has been reduced to a child-like state and is having to relearn life.

"Seeing Tom so upset and down-trodden about his physical abilities, knowing he will never be as competitive as he was, is heart-breaking.

"He is Tom but a different Tom. There are many bits of him that are there but consumed by the new, difficult Tom, and it is hard to deal with. Things are very different now."

Mr Forbes told the court there was no evidence that Mr Bell had ridden in anything other than a 'careful and competent' manner.

The Lexus however was said by witnesses to have 'come out of nowhere' and into the middle of the junction, hitting the motorbike.

"There was a deliberate decision to ignore, or a flagrant disregard for, the rules of the road in accelerating towards and through a red traffic light," said the prosecutor.

Those who tended to Mr Bell before paramedics arrived included an off-duty police officer and a merchant seaman trained in first aid.

Mockford, who has previous convictions and cautions for attempted kidnap and common assault, was heard asking 'What have I done?', but claimed he was driving between 40 and 45mph.

Nicolas Maggs, defending, said his married client was 'deeply sorry' for the consequences of his 'bad decision' that day.

Urging the court to impose a suspended sentence, he added: "This is an example of someone trying to catch the light and accelerating when he should be braking.

"It was a road he knew well and used regularly going to and from work. He didn't set out that day to hurt anyone but simply made, for a moment at speed, a very poor decision and is profoundly sorry for the consequences."