An elderly couple died when their car somersaulted into the path of another on New Year's Eve, an inquest heard.

Alan and June Thomsett, of Horsham Road, Findon, both suffered severe back injuries in the crash last year, which launched their green Mitsubishi Colt across the central reservation of the A24 and into oncoming traffic.

Experts suspected retired domestic appliance engineer Mr Thomsett may have had a heart attack and lost control of the car but they could not be sure.

West Sussex coroner Roger Stone ruled Mrs Thomsett's death was accidental but recorded an open verdict for Mr Thomsett because it was unclear whether it was his heart condition or his injuries which killed him.

The couple, who had been married for 46 years, where driving south along the A24, approaching Findon roundabout, when the car suddenly crossed into the central reservation, smashed into a tree and flipped on to its roof, landing in front of a northbound Jaguar XJR.

Both died at the scene. The Jaguar driver escaped serious injury.

Witness Julie Worrall, from Haywards Heath, was driving her Volvo car behind the Thomsetts when the crash happened, at about 2pm.

She said: "We were nearing the north of Findon roundabout and I was talking to my husband about how crash barriers had been introduced on the A24 further north.

"The Mitsubishi was in the inside lane. There was a corner and it went straight into it.

"There were no brake lights, it did not swerve and did not take any corrective measures.

"My immediate reaction was the driver must have had a heart attack.

"The front side of the car struck something, it somersaulted and I heard a loud bang."

Her husband Roger Worrall, who called the emergency services, said: "As the road went round to the left, I suddenly became aware the car in front was going straight on.

"We passed the car just before it went upside down and on to the northbound carriageway."

Dr James English, from Washington, was driving his Jaguar when the Thomsetts' car landed directly in front of him.

He said: "I was travelling north and was in the outer lane. I had just passed four cars from the roundabout before and was travelling at approximately 60mph.

"Quite without warning, I saw a blur. It came from above and into the road in front of me.

"It was 15 feet away, I had no time to react apart from just bracing myself and holding on to the steering to keep going straight.

"It was like the car was coming down on the nose of my bonnet."

Pathologist Dr Mark Appleton confirmed Mr and Mrs Thomsett had sustained severe spinal injuries in the crash but Mr Thomsett may have died from a serious heart condition.

He said: "He had severe narrowing of all three main vessels supplying blood to the heart, a very common cause of sudden, unexpected death.

"The spinal injury would have been fatal but there was severe underlying heart disease.

"It suggests a sudden collapse at the wheel precipitated the accident.

"There is a strong possibility he may have died at the wheel prior to the spinal injury but I cannot be absolutely specific."

Crash investigator PC Colin O'Neill agreed Dr English would not have been able to avoid the impact and told the Thomsett's daughter, Caroline Thomsett, that crash barriers were being introduced along the A24 but money was yet not available to install them near Findon.

PC O'Neill said that Mr Thomsett "had simply not reacted, no brakes were applied or any steering from it".

He added: "Generally, there is a very high likelihood in a collision that there should be some response of braking.

"The passenger would not have been in a position to realistically take any action because the time frame would have been very small.

"The cause of collision lays on the car crossing the carriageway.

"It's indicative of a driver being taken ill at the wheel.

"The A24 is being revamped from top to bottom and it has been recognised that there are problems with various aspects of it.

"It's not the road, it's the peoplelosing control.

"There is an element of money involved, there is a finite amount of money to pay for safety schemes.

"That particular section of the A24 will have barriers in the future.

"I think Dr English was lucky to escape injuries, probably a result of driving the type of car he does."

Miss Thomsett, from Oxfordshire, said after the hearing that she thought speed barriers at the bend where the crash happened might have saved lives.

She said: "There had been a delay in introducing speed barriers because of financial reasons.

"It's too late for my parents.

"Money should be found to save other people.

"There is a councillor who I am in contact with and I am looking to try to get something done."