Airbus Says Speed Sensors Should Be Replaced

By Edward Cody
Washington Post Foreign Service
Saturday, August 1, 2009

PARIS, July 31 -- Airbus said Friday that airlines flying its A330 and A340 long-haul jetliners should replace most of the planes' external speed sensors that investigators suspect may have played a role in the crash of an Air France A330 on June 1.

The recommendation, conveyed to airlines around the world Thursday, reinforced suggestions that the widely used pitot tubes, tiny devices affixed to the skin of the aircraft to measure airspeed, were shown to be unreliable when Air France Flight 447 from Rio de Janeiro to Paris plunged into the Atlantic, killing all 228 people aboard.

Airbus spokesmen told reporters the recommendation would affect about 200 aircraft in service for a variety of airlines.

Any hint as to what caused the June 1 crash was considered highly sensitive because it could affect the business of airlines using the A330. In addition, some of the victims' families have accused Air France and Airbus of withholding information and have lined up law firms to prepare what are likely to be multi-million-dollar claims for reparations.

France's Investigation and Analysis Bureau, which is trying to find out what caused the Air France crash, said July 2 that the apparent icing-over of the A330's pitot tubes was a factor in the plane's sudden drop from the sky but that other factors -- lightning, wind, hail or other equipment failure -- were also probably part of the deadly equation.

Despite two months of searching, French and Brazilian authorities did not find the black boxes for Flight 447, leaving investigators to search for clues in piles of debris collected from the ocean's surface and flown to Airbus headquarters at Toulouse.

Simultaneous to the Airbus announcement, the European Aviation Safety Agency said it will soon issue a directive that all airlines flying into European airports should have at least two U.S.-manufactured Goodrich speed sensors out of the three sensors that are standard equipment on Airbus planes. The agency's planned directive mirrored the recommendation made by Airbus itself.

Many airlines, including Air France, had used sensors manufactured by the French company Thales on their Airbus planes. Thales, a large firm that manufactures high-tech machinery and military equipment, declined to comment on the new recommendations.

An Air France pilots' union called last week for replacing the Thales sensors with Goodrich sensors on all Air France planes. The pilots were responding to another incident, this one on an Air France flight from Rome to Paris, in which the pitot tubes apparently iced up and transmitted false data to the cockpit.

A burst of automatic messages sent out by the doomed Air France A330 showed that gauges designed to show airspeed were receiving inaccurate data, according to airline investigators. Some French pilots suggested inaccurate readings could have led the pilots to fly into a violent storm at an inappropriate speed, hindering their ability to control the plane against strong winds.

Since the accident, Air France has speeded up an expensive replacement program for the speed sensors, equipping all of its planes with the new Thales pitot tubes. But in a statement, the airline said it would follow the Airbus recommendation.

© 2009 The Washington Post Company