A contractor found guilty of health and safety breaches at Luton Airport after a Norfolk pensioner died on a pedestrian crossing has won the first stage of a bid to have the convictions overturned.

Mary Whiting, 78, of Windsor Chase, Taverham, was killed after being hit by a milk lorry while crossing an access road, which had been redesigned following a terrorist attack on Glasgow Airport.

She was returning from a family holiday when the collision happened in May 2009.

C-T Aviation Solutions Ltd, which was involved in the redesign, was fined £70,000 and ordered to pay £30,000 costs after being convicted of two breaches of health and safety rules.

The company was convicted at Luton Crown Court in May last year.

But C-T Aviation has now been given the go-ahead for an appeal after top judges ruled it was 'arguable' that the tragic event was the result of 'ordinary, everday risk' and not because of anything the contractor did.

The court heard Mrs Whiting died as she followed her great-granddaughter over the crossing.

The driver of the lorry was prosecuted in 2010 but was found not guilty of causing her death by careless driving.

London Luton Airport Operations Ltd, which runs the airport, and C-T Aviation were both prosecuted by the Health and Safety Executive.

The airport operator was fined £75,000 and ordered to pay £197,595 costs after it too was found guilty of health and safety breaches.

Lawyers for C-T Aviation, based in Barnes, south west London, argued the convictions were 'unsafe'.

The judge should not have left the case to the jury as there was not enough evidence on which the company could be found guilty as charged, they said.

Prashant Popat QC, for the contractor, said the 'forseeable risk' of an accident was no more than the risk of a similar incident happening on any other crossing.

The barrister added: 'It was an incident of the type that, sadly, occurs on highways every day.

'This was a clear crossing on a clear day.'

No date was set for the full hearing of the appeal.