A light aircraft has crashed at Cotswold Airport in Gloucestershire.
A Great Western Air Ambulance spokesman said the aircraft appeared to have crash-landed and caught fire just before 15:00 BST.
The 48-year-old pilot suffered serious burns and was flown to Frenchay Hospital in Bristol. The man's family have been told.
Kemble Airfield, near Cirencester, was opened by the RAF in 1938 and was renamed Cotswold Airport in 2009.
The pilot was the only person on board, police said.
A Gloucestershire Fire and Rescue Service spokesman said the aircraft was a North American Bronco plane.
Witness Derek Johnson, from Chippenham in Wiltshire, said: "I was talking to this couple who parked up at the same time as me, I got out of the car, there was a great big bang, a big puff of black smoke."
The Great Western Air Ambulance Charity (GWAAC) spokesman said: "The GWAAC aircraft landed at Kemble Airfield at 3.15pm, at approximately the same time as Wiltshire Air Ambulance.
"A light aircraft did appear to have crash-landed and had suffered subsequent fire damage.
"GWAAC medical staff anaesthetised the patient ahead of transport to Frenchay Hospital in the Wiltshire Air Ambulance aircraft."
A Wiltshire Police spokeswoman said an investigation would be carried out into the cause of the crash.