A grandfather celebrating his brother’s 60th birthday died at a go-kart track after his daughter-in-law crashed into the back of his kart, an inquest heard.

Allan Fairweather, 63, suffered a traumatic chest injury after he was flung 12 metres from his vehicle at Ellough Park Raceway, near Beccles, and died at the scene on September 25 2016.

An inquest in Ipswich was shown CCTV footage of the lead-up to the incident, which happened on the finish straight during the final lap of a six-lap practice race.

His daughter-in-law Peggy Fairweather is seen rounding the final bend and overtaking another driver, Adam Rouse, on the finish straight before crashing into the back of Mr Fairweather’s kart.

Tony Burgess, environmental health officer for Waveney District Council, talked jurors through the CCTV video.

He said: “Peggy glanced to her left where there was another driver, Adam Rouse, who she was in the process of overtaking.”

Relative Emily Fairweather, who was watching from the trackside, said she saw two karts turning into the finish straight where Mr Fairweather’s kart was stopped.

“I was worried they wouldn’t see the kart stationary,” she said. “They were alongside each other.

“I yelled ‘why aren’t they looking ahead?’.”

She continued: “I saw a person eject from the kart along with a booster seat. It looked like the kart exploded. My heart sank.”

Shirley Fairweather, whose husband Richard Fairweather was celebrating his 60th birthday, was with Emily on the trackside.

“Two karts were overtaking each other, they glanced at each other,” she said. “Emily said ‘why aren’t they looking at each other?’. I said ‘they’re not going to stop’.”

Sara Ansdell, Mr Fairweather’s niece, said she was in the race viewing area when she saw Mr Fairweather round the final bend before two more karts going “quite fast”.

She said she looked away as a child she was with asked her a question, then she heard a loud bang and looked back.

“One driver was on the track clutching their arm, another one was rolling down the track and this driver stopped moving and was then motionless,” she said.

The inquest into the death of Mr Fairweather, of Oulton Broad near Lowestoft, Suffolk, is listed to take five days.