A pig farmer has won almost £40,000 in compensation after a low-flying hot air balloon caused his outdoor herd to stampede in terror.

The incident took place in April 2012 at Dan Gilbank’s Low Moor Farm, Sand Hutton. But the two year battle which called on eyewitnesses, solicitors and a maths professor has only just concluded.

Mr Gilbank told Farmers Weekly that three sows and a boar died from heart attacks when the balloon flew so low it needed to use its burners to clear nearby trees.

“We had been feeding the pigs at about 10am when the balloon appeared. He was so low I thought he was looking to land in the pig field. It was when he hit the burner to clear the trees that our pigs went mad. They all stampeded to one end of the field and piled into a ditch.”

The four animals died instantly from heart attacks, but it was the knock-on effect of the incident which saw losses mount at the 620-sow unit.

“Immediately after the incident six sows aborted. By the time we came to the normal farrowing date 70% of the two batches in the field either aborted or produced stillborn litters.

”That meant the total loss was about 500 pigs.”

But the balloon company Wiltshire-based Go Ballooning claimed it was 800m away and had GPS readings to prove it.

Mr Gilbank called on legal firm Langleys Solicitors to help.

The firm’s head of dispute resolution Darren Morgan took up the fight.

“The Civil Aviation Authority has a clause which refers to compensation being payable when noise in the sky creates damage on the ground,” Mr Morgan said.

But the balloon company would only offer £10,000 compensation because it said it was 800m away.

“We calculated that the losses in livestock came to £70,000 so the figure offered was far too low. Even though we had photographs from eyewitnesses and the testament of the farmer and farmworkers that the balloon was far closer than claimed, we had no way of proving it,” he added

It was then that Mr Morgan had a brainwave and asked the University of York’s maths department to analyse the eyewitness photographs to establish the exact location of the balloon.

York’s maths professor Chris Fewster explained how he used trigonometry to work out where the balloon was and debunk claims that it was further away from the pigs.

“It wasn’t too difficult. We knew where the photograph had been taken, the size of the balloon and the height of the trees,” Prof Fewster said.

“In the photograph the balloon appears behind the trees so it looks a long way away. But the balloon is enormous, at 27.5m across, so it is further away than it appears.

“The calculations using basic trigonometry showed that the balloon was indeed closer to the pig herd than the company claimed,” he said.

The ballooning company admitted liability and paid out £38,000 to Low Moor Farm. Darren Morgan told Farmers Weekly that the figure was settled without needing to go to court. “We claimed for £70,000 but the company successfully argued that there would be reductions in feed costs and labour reducing it to the final agreed sum,” Mr Morgan added.

Go Ballooning has ceased trading due to issues unrelated to the incident and was unable to comment.

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