The Luxembourg-registered plane appeared to be 'looping' and to have turned upside down before impact.
The plane, a single engine propeller aircraft, crashed into the field west of the A44 road. A section of the road has been closed between Bladon and Langford Lane in Kidlington.
Eyewitnesses described how all seemed to be normal as the aircraft approached the airport at about 11.20am.
Pilot Mark Coombs, from Charlbury, was driving south on the motorway when he saw the plane come down.
'The aircraft appeared to be making a fairly normal approach at about two to three hundred yards before the end of the runway.
'It made a level left turn and rolled to the left and then went down, almost spiralling in perpendicularly. It looked like it was coming in to land, as if it was almost five seconds away from landing.'
Mr Coombs, who works for Air Med air ambulances, added: 'When I saw the accident, I did think there was no chance of any survivors.
The bodies of the three victims were removed from the wreckage of the plane and a small tent was been erected over them in the field. It is expected that the bodies will remain where they are overnight.
For Flemish readers only:
De piloot is een Nederlandstalige inwoner van Vlaams-Brabant. De
Fransman, Paul-Louis Halley, was één van de belangrijkste aandeelhouders van winkelketen Carrefour.
