Former Buckingham Rugby player Lee Gregory will take part in the Tough Mudder Challenge in April in memory of his late father, Steve.
Steve Gregory, who worked as a motorcycle training instructor in Brackley, collapsed on the side of the A43 near Towcester in September after pulling over.
He was treated by emergency services, but was pronounced dead after being airlifted to hospital.
Lee, a senior aircraftsman based at RAF Wyton, Cambridgeshire, is taking part in the challenge to raise money for the Warks and Northants Air Ambulance who helped his father.
He said: “I am trying to raise awareness that the air ambulance is not a Government-funded organisation and to make sure people don’t take them for granted.
“The air ambulance service relies on donations to keep going yet still takes on around 1,000 missions a year, with each costing £1,400.”
The Tough Mudder Challenge is a 10 to 12 mile assault course, with miltary-style obstacles designed by British Special Forces that challenge stamina, strength and mental attitude.
Lee also plans to tackle the 69-mile Hadrians Wall in a day test, and then to windsurf the English Channel in September for the same charity.
Lee has appealed for road users to donate £1 to the Air Ambulance by texting RSIG64 £1 to 70070. To donate, visit www.justgiving.com/Lee-Gregory64.