A couple plan to break the speed record for flying a piston-engined aircraft from Land's End to John O'Groats.
Amputee John de Frayssinet and Jenny Ayers, who have mobility problems, have built their own fibreglass plane over the past seven years.
They want to enter the record books by covering the 621-mile (999km) course in just over three hours.
The pair are both members of the Cotswold Aero Club, based at Gloucestershire Airport in Churchdown.
Mr de Frayssinet, 59, said he and his wife were waiting for a clear day in May before taking off from The Navy air station at Culdrose, Cornwall.
"I'm missing one leg and the purpose of this attempt is to get the word out to other disabled people that you can go and fly and become a pilot, he said.
"It's one of the few things you can do where you really aren't disabled."
The pilot operates the pedal in the two-seater aircraft, which is capable of reaching 275mph, using a special shoe with a hook on it.