June 6, 2009

Among them may have been the plane's autopilot, which was disengaged for the final minutes before the plane is believed to have plunged into the sea. But officials said it was not clear whether the autopilot had been switched off by the pilots, or had cut out because it received conflicting airspeed readings.

The mystery over what happened to flight AF447 deepened when French weather experts said there was no evidence the aircraft had encountered "exceptional" atmospheric conditions.

The Airbus A330-200 flying from Rio to Paris disappeared without trace over the Atlantic on Sunday night with 228 people on board.

Reconnaissance planes and ships have failed to find any debris or bodies from the plane or even identify where it went down.

Advanced acoustic equipment on loan from the Americans is being installed in two French vessels and France's nuclear submarine, The Emerald, is joining the search.

At a press conference at Le Bourget Airport on the outskirts of Paris, Alain Ratier, deputy director general of Météo France, the French weather centre, said there was "nothing to indicate" that flght AF447 had encountered "a storm mass of exceptional intensity".

He was basing this, he said, on the level of infrarouge satellite imaging in the zone where the plane disappeared. He said there was a "powerful cumulo-nimbus" in the zone but this has already started to weaken before the aircraft reached its supposed passage. He insisted there was nothing to suggest weather of a "exceptional nature" in the zone for the time of year and pointed out that the storm activity was for example much heavier on the African coast at the time.

Paul-Louis Arslanian, director of the Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA) said accoustic listening equipment borrowed from the US is being installed on two ships currently approaching the search area. This gives the French three methods of search: an ordinary warship, the nuclear submarine Emerald and the ships carrying the acoustic gear. Mr Arslanian said the aim was to "cover as quickly as possible and as systematically as possible the greatest possible area."

"We're not going to be just looking anywhere," he explained saying the depth of the ocean in the search zone is estimated at 4,606 meters.

Mr Arslanian, who earlier this week said he "wasn't very optimistic" about finding the black boxes, added that even if they were found it was possible they were damaged and no longer connected to the flight recorders.

The BEA said the automatic messages sent by flight AF447 revealed contradictory speed measurements.

In Brazil, investigators said the search for debris, bodies or the slightest proof of the exact spot the plane crashed would continue "right up to the time when it would be humanly impossible to find anything". But five days after the plane disappeared experts fear any significant debris will already have sunk to the bottom of the ocean.

www.telegraph.co.uk/news/worldnews/europe/france/5460291/Air-France-

plane-doomed-French-jet-sent-out-24-system-failure-alerts-before-disappearing.html