Air France's remaining five Concordes are now out of service

The five remaining Air France Concordes have not flown since the Paris disaster.

British Airways, the only other airline which operates Concordes, grounded its seven-strong fleet after the accident, but the planes resumed service the following day, after safety checks.

An Air France statement said: "No debris from inside the engine has been identified. The fire appears to have started outside the engines but this remains to be determined."

The airline has also announced preliminary compensation payments for the families of those who died in the disaster - the first fatal accident involving the world's only supersonic passenger jet.

Tyre warning

In Washington, the National Transportation Safety Board (NTSB) has released details of four incidents in the US between 1979 and 1981 in which Air France Concordes blew tyres on take-off and produced a "potentially catastrophic" situation.

The NTSB recommended at the time that each tyre and wheel be inspected before take-off, and that if a problem was suspected during take-off, the landing gear should not be retracted.

The chief French accident investigator responded that it was already Air France procedure not to raise the landing gear, and in such a case, an immediate landing must take place.

Speculation about the Paris disaster has centred on the possibility that debris from a damaged tyre or wheel could have been sucked into the engine.

Long process

Prosecutor Xavier Salvat, who is heading the judicial inquiry, said he intended to determine the causes of the accident quickly.

But he acknowleged that the inquiry could take months.

All the bodies have been recovered, but investigators are continuing to sift through the charred debris of the Concorde on the edge of the suburban town of Gonesse.

Reports suggest the Concorde was unable to raise its landing gear

Citing information from the two flight recorders, investigators say:

• One of the engines failed outright
• The other engine on the same wing lost power twice
• The Concorde's landing gear jammed before it crashed.

The airline has provided counselling for the ground staff who worked on the Concorde immeditately before its take-off.

Compensation

Air France announced it would make a preliminary payment of 140,000 francs ($20,000) to relatives of crash victims "for their immediate material needs", and would pay for funerals and any psychological treatment the families might require.

But Thilo Schmidt from the German Transport Ministry told the BBC that the victims currently "have other things on their minds than suing anyone, that is something we face later".

Residents of Gonesse are to hold a memorial procession for the crash victims on Friday.

The accident has drawn fresh attention to the danger posed by aircraft to the town, which lies in the flightpath of more than half of flights that leave Charles de Gaulle airport.