Lawyers for Air France's insurance companies are in talks with the families on the release of a first tranche of €17 500, said Pierre-Henri Gourgeon.

"We are at this stage focused on a first advance that will be paid out to each victim: about €17 500," Gourgeon told RTL radio.

He also said Air France was trying to organise a memorial for the grieving families and that an announcement on a ceremony was expected in the coming days.

The Airbus A330 came down on June 1 as it was flying from Rio de Janeiro to Paris. The cause of the disaster is not known.

All 228 people on board are presumed dead, and 50 bodies have so far been recovered, along with the plane's tail fin and hundreds of other parts and pieces.

Air France has drawn up a list of 1800 people who have lost a family member in the crash and are in regular contact with them, said Gourgeon.

"The entire company was deeply affected by this accident and remains mobilised," he said.

There were passengers from 32 nationalities on the flight that crashed off the coast of Brazil, the worst disaster in the airline's history.

French and Brazilian navy ships, backed by more than a dozen aircraft, have been scouring waters 1000 kilometers off Brazil's coast for remains and wreckage of the plane.

Black boxes still lost

A French nuclear submarine and two vessels equipped with underwater listening devices are also trying to pick up the homing beacons of the plane's black boxes, which would be vital in determining the flight's final minutes.

Speculation on the cause of the disaster has focused on the plane's airspeed monitors, which may have malfunctioned.

The airliner went down as it was flying through turbulence caused by a storm and the jetliner sent out 24 automated messages about abnormalities in the final minutes of the flight.

French investigators said the plane's airspeed sensors, or pitot probes, had been feeding inconsistent readings to the cockpit.

Conflicting airspeed data can cause the autopilot to shut down and in extreme cases the plane to stall or fly dangerously fast, possibly causing a high-altitude breakup.

But the French bureau leading the investigation, along with Airbus and Air France, have insisted there is yet no firm evidence linking the speed monitors and the crash.

Air France has upgraded all sensors on its long-haul fleet as precautionary measure after protests from pilots.

AFP