Air France Speeds Up Maintenance Following Crash
Airline Replacing Speed Sensors on All its Airbus Jets
Jun 8, 2009
The sensors help ensure that the jet is not flying too fast or too slow for conditions. A jet flying too slow can stall and go into a potentially irreversible dive. A jet flying too fast can exceed its design limitations and break apart.
Airline Knew of Sensor Problems
Investigators say minutes before the Airbus A330 disappeared a week ago, the speed sensors were transmitting faulty data. This is not a new problem. In a statement released Saturday, Air France reported that it began noticing problems with speed data on A330s and A340s a year ago. The problems were specifically related to a piece of equipment called a Pitot probe (see "What the Heck Is a Pitot Probe?").
“Starting in May 2008, Air France experienced incidents involving a loss of airspeed data in flight, in cruise phase on A340s and A330s,” the statement noted. “These incidents were analyzed with Airbus as resulting from Pitot probe icing for a few minutes, after which the phenomenon disappeared.”
Though near the Equator when it disappeared, Flight 447 was flying at an altitude where temperatures can easily facilitate icing, particularly in a moisture-laden environment like a storm.
Airbus Balked at Changing Sensors
Air France discussed the problem with Airbus, but the manufacturer initially did not have a solution, according to the airline, even though a similar problem with the A320 model caused Airbus to recommend replacing the Pitot probes with a new design. The A320 problem was related to “water ingress at low altitude,” not icing at high altitudes.
Nevertheless, laboratory tests conducted in the first three months of this year indicated that the new Pitot probe design might be beneficial in eliminating the icing problems plaguing the A330 and A340 models. Airbus recommended “an in-service evaluation in real flight conditions.” Air France, though, decided to go ahead and replace all the Pitot probes without waiting for further testing. It began replacing the probes five weeks before the crash of Flight 447.
Air France was quick to point out that it is not making an assumption on the cause of the accident. However, the company announced its intention to speed up the process of replacing the Pitot probes on its remaining A330 and A340s.
In other developments Monday, Brazilian military officials reported recovering eight more bodies at the crash site in the Atlantic Ocean, about 900 miles northeast of the Brazil coast, bringing the total number of bodies recovered to 24.
A large section of the aircraft's tail also was recovered, raising hopes that the jet's "black boxes" also might be found. Recovering the flight data recorders is considered key in discovering the cause of the accident, which is believed to have caused the deaths of 228 people.
