The appeal was set up by contributors to an internet forum based at online motoring magazine PistonHeads.com and initially only expected to raise a few thousand pounds.

But now YAA’s chief executive, Martin Eedes, said so much money had been raised that it would use the donations to help buy a second helicopter for the service.

He said on the appeal website: "YAA will be designating Richard’s fans’ donations for "Hammy’s Heli" so that we can expand our work and advance our plans for a second helicopter."

Mr Eede said there had always been a long term plan to buy a second helicopter for Yorkshire, but this strategy was now being "brought forward" because of the success of the appeal.

He said: "We thought this was the right way to mark the response from fans of Richard Hammond."

However, he added that those wishing to donate to the appeal should also search for their local air ambulance charity and "support them too".

Hammond, 36, was flown by the YAA’s current helicopter to Leeds General Infirmary in a matter of minutes after the jet-powered dragster he was driving crashed on an airfield near York. Medical staff at the hospital said his recovery was continuing as he recuperated on a general ward after being transferred from a high dependency unit.

Top Gear host Hammond ’walking’ - Sept 23, 2020
Top Gear star Richard Hammond got to his feet and walked, just 30 hours after his high-speed crash, his co-presenter Jeremy Clarkson has said.

The 36-year-old is in a stable condition at Leeds General Infirmary where friends and family have been keeping a bedside vigil following Wednesday’s accident at Elvington airfield, near York.

Clarkson, a Sun columnist and Hammond’s co-presenter of the motoring show, said in the newspaper: "In the wee small hours of Thursday night, just 30 hours after what is almost certainly the world’s fastest ever car crash, Richard Hammond suddenly sat up in bed, opened his eyes and asked what had happened."

Clarkson, who told him he had been in a car accident, said that Hammond then got out of bed and walked shakily to the lavatory.

The presenter was seriously injured when the jet-powered car he had been driving at speeds up to 300mph crashed.

Police and Health and Safety Executive investigations are continuing to establish exactly what went wrong in the incident which happened during filming for the BBC2 show.

The BBC has released no further information about the events leading up to the crash.

The hospital said Hammond suffered a "significant brain injury". Earlier a spokesman added: "Doctors say Richard Hammond is making satisfactory progress.

Top Gear’s Richard out of intensive care - Sept 22, 2020
Doctors treating Top Gear presenter Richard Hammond said today his condition has improved and he has been moved out of intensive care. The TV star is now said to be in a "stable" condition following his high speed crash in a jet-powered car.

A spokesman at Leeds General Infirmary said: "Doctors say Richard Hammond is making satisfactory progress. "This morning he has been moved from intensive care on to a high dependency unit. "His condition has been downgraded from ’serious but stable’ to ’stable’."

Doctors last night said Richard’s injury gave them "cause for concern" but added that they were "reasonably optimistic" he would make a good recovery.

Top Gear’s Jeremy Clarkson yesterday paid tribute to the father-of-two as he visited him in Leeds with co-presenter James May.