A wheel hit and killed an 84-year-old woman after falling off a badly-maintained farm trailer, a jury was told.

Doris Smith, 84, had been walking a neighbour's dog along Ashingdon Road, Rochford, when a tyre fell from the 40ft trailer and careered across the road, knocking her unconscious.

Mrs Smith suffered a wound to her head and a severely injured left leg and was taken to Southend Hospital, where she died a few hours later, Chelmsford Crown Court was told.

John Dodd QC, prosecuting, said the accident happened because brothers Howard Baker, 56, and Martin Baker, 54, and the driver, Lewis Windust, 66, did not make adequate checks on the vehicle before driving it to Southend Airport to cut the grass there.

He said: "She would have had no warning and no chance of escape.

"The pavement was quite narrow and she probably heard nothing before the wheel ploughed into her."

Mr Dodd added: "All three bear criminal responsibility for the death of Mrs Smith due to the use on public roads of a vehicle that was in no fit state to be used because it was in a dangerous condition."

He told the court the three defendants had failed in their duty of care because subsequent checks of the vehicle found a vital locking nut was missing as well as a number of wheel nuts from the other wheels.

The accident happened on July 11, 2005, when Windust drove the tractor from RGA Baker and Co, based at Lovedown Farm in Rochford.

The court was told Windust was travelling in convoy behind a similar tractor and trailer driven by Howard Baker when two linked wheels fell off.

The men carried on their journey to Southend Airport and were followed by a witness, Colin Crown, who told Howard Baker the wheel had flown off and hit a woman.

The court heard Howard Baker did not return to the scene because he said he could not drive there.

He declined a lift from Mr Crown.

However, he informed airport security about the accident.

Mr Dodd told the court Howard Baker then lied to police by giving them a statement claiming he was the driver of the faulty vehicle.

Howard Baker later owned up saying he lied because Windust lived in New Zealand and had been staying with him on holiday, the court heard.

Howard Baker, 55, of Marsh Road Tillingham, and Martin Baker, 53, of Lower Road, Hockley, both pleaded not guilty to manslaughter.

Lewis Windust, 65, from New Zealand, pleaded not guilty to dangerous driving.

The trial continues.