Air France Flight 447 was brought down by a "convergence of different causes," although it's too early to know what they are, the head of Airbus' parent company said.
Airbus made the A330-200 plane flown by Air France that crashed May 31 with 228 people on board en route to Paris from Rio de Janeiro. Industry experts have called the plane one of the safest in the world.
"In such an accident, there is not one cause," EADS CEO Louis Gallois said in comments held for release on Sunday.
"It's the convergence of different causes creating such an accident."
Investigators have focused on the possibility that external speed monitors, called Pitot tubes, iced over and gave false speed readings to the plane's computers as it ran into a turbulent thunderstorm.
Air France ordered these Pitot tubes, which are made by France's Thales Group, replaced on long-range Airbus planes on April 27 after pilots noted a loss of airspeed data in a few flights on Airbus A330 and A340 models. Pitot tubes on the jet that crashed had not been replaced yet.
But Gallois said investigators "don't know if Pitots are part of the accident."
"We know that Thales has improved its Pitots with a new one because they had some problems with water at the takeoff and landing," he said.