Speed instuments 'due for replacement'

French crash investigators say Air France had speed monitors that were due to be replaced.

French crash investigators said today that the Air France jet which plunged into the Atlantic had speed monitors that had often failed on other planes and were due to be replaced. The head of the air accident investigation agency said the missing Rio to Paris flight, which crashed on Monday with the loss of all 228 people on board, had suffered multiple systems failures in its final moments. Automatic error messages broadcast by the A330 jet just prior to the crash showed that its autopilot had cut out after it received conflicting speed readings, a BEA director Paul-Louis Arslanian told reporters.

"There is a programme of replacement, of improvement," he said, adding that planes that have not yet had the replacement are not necessarily dangerous, and that in other cases pilots had been able to regain control. On Friday, Airbus urged all pilots of its jets to review a warning issued in July 2001 on the procedures to follow if speed indicators give conflicting readings and force the autopilot to cut out.

Investigators seeking clues to what had caused flight AF 447 to crash so suddenly have so far had to rely on the automatic messages as salvage crews have been unable to locate the wreckage in deep Atlantic waters. Brazilian air force spotters believe they have identified floating debris, but no surface vessel has been able to recover any, and a French nuclear sub and a research ship equipped with mini-submarines are steaming to the scene.

Early speculation as to the cause of the accident focused on foul weather, as the jet was flying through a thunderstorm, but Mr Arslanian said the conditions had not been exceptional for the region. He also played down the idea that a terrorist bomb might have destroyed the plane, saying that the 24 error messages showed the on-board electronic systems including the autopilot had shut down one by one.

But he did not formally rule out an attack: "Really, that would be truly astonishing, but that's not to say it is 100 per cent impossible." Meanwhile, intense search operations continued 1,000 kilometres off Brazil's north-east coast, as salvage teams attempted to locate the black box flight recorders which might solve the mystery. Five more Brazilian navy vessels were already in the area, which was being overflown by 12 Brazilian and French aircraft, and the French submarines and research vessel were heading to the area.

The head of air traffic control for the area, Brazilian Brigadier Ramon Cardoso, told reporters "we have not made any recovery of material." Some items spotted floating in the vicinity were "not relevant," he said, adding that weather conditions were terrible, limiting visibility, and currents had changed direction. Brazilian officials said items picked up Thursday turned out on closer inspection to be nothing more than trash, probably from ships.

Brig Cardoso said the objects spotted from planes might have since sunk to the bottom of the ocean, where the plane's black boxes are also believed to be. While the investigation cast about for clues, families of those on board the plane expressed frustration with the lack of physical evidence that their loved ones were gone forever. A group of 10 Brazilian relatives were flown from Rio to the main search operations centre in the Brazilian city of Recife on Friday to speak to a pilot involved in the search for the plane.

They left without speaking to media, and returned to Rio where another service was held in memory of the Air France passengers and crew. A British law firm is investigating the loss of Air France 447 in the belief that it may be linked to another accident involving an Airbus 330 jet, it said on Friday. Stewarts Law LLP is already acting for passengers injured on October 7, 2008, when a Qantas A330 plunged suddenly mid-flight before pilots regained control, an incident it thinks similar to Monday's crash.

An investigation into the previous accident showed it was caused when the Australian A330's flight computer gave incorrect information to the autopilot, causing the plane to plunge into an almost catastrophic dive. An Airbus spokesman insisted there were no similarities between the Qantas and Air France accidents, telling AFP that the latter jet was fitted with an ADIRU from a different manufacturer.

Also in Rio, police began collecting genetic samples from relatives of the passengers on the doomed flight in order to accelerate the identification process should any remains from the crash be found. *AFP