The runway at Charles de Gaulle had been carefully swept before take-off. Initial reports by the team investigating the disaster said it was caused by a small strip of metal from the engine of an American airliner which had taken off minutes before. The metal punctured a tyre, blasting debris into the wing, causing fuel tanks to rupture and ignite. The tests concern the aircraft's performance on the ground. They include simulating fuel leaks under the delta wings, using colored fuel and cameras to track the flow.
Flight tests are due to take place in Britain.
British Airways and Air France officials are cooperating closely. The highly publicised program is an indication of the French Government's determination to get Concorde, which is still a great symbol of national pride, back in the air. Jean-Claude Gayssot, the Transport Minister, said on Sunday that the airliner could be in service by the end of the year. BA is fitting one of its fleet with new fuel tank liners made of rubber and Kevlar, a dense fibre used in military vehicles and racing cars. BA aircraft will be used for the air tests.