David Philpott, chief excutive of Wiltshire Air Ambulance, will be swapping his suit and desk for walking boots and a rucksack when he takes on the full 55-mile White Horse Challenge this July.

Mr Philpott, 56, of Seend, will undertake the gruelling two-day countryside hike, which takes in seven of the county’s white horses on July 5 and 6.

Now in its ninth year, the challenge has raised more than £97,000 for the air ambulance appeal.

Mr Philpott will lead a team of staff, trustees and volunteers from the charity who will also undertake some or all of the challenge. So far six have signed up but it is thought there will be more.

Calling themselves ‘On White Horses’, after the 1970s TV show and chart-topping hit, together they hope to raise £1,000.

The challenge is organised by Wiltshire and Somerset based chartered accountants and financial advisors Monahans, plus Rygor Group, a dealership for Mercedes trucks and vans based in Westbury and Rocking Horse Nursery based in Shaw, and is sponsored by The Wiltshire Times and the Gazette & Herald.

The choice of walks ranges from a seven-mile family challenge on the Sunday up to the whole 55 miles over two days. The challenge can be completed individually, as part of a team or as a relay. Walkers can also bring their dogs.

Mr Philpott said: “We cannot thank the organisers, sponsors and participants enough for continuing to support this fantastic fundraising event.

"The funding we need to keep Wiltshire Air Ambulance flying is set to rise at the end of this year when we take delivery of our new helicopter and from January 2015 we will need to find £2.5 million to keep this vital, life-saving service operational.

“I’m training hard and walking 15 miles a couple of times week. I’m really looking forward to walking through the glorious Wiltshire countryside and hoping for good weather.

"I hope many more teams and individuals will join us for this challenge which has raised a truly incredible amount over the years.”

Zoe Meaden, from Monahans, said: “We are delighted that the Wiltshire Air Ambulance are entering a team. The event is open to everyone and I would encourage anyone who is interested in taking part to contact me.”

For more information and to register for the challenge, visit www.whitehorsechallenge.co.uk or contact Zoe Meaden on 01225 785520, or email Zoe.Meaden@monahans.co.uk