French pilot union Alter is urging its members not to operate Airbus A330/340 aircraft that have yet to be equipped with modified pitot probes, in the wake of the South Atlantic Air France accident.
The union, said to represent around 12% of Air France flight crew, issued the guidance to its members following the airline's decision in April to gradually change pitot probes on its A330/340 fleet following a spate of incidents last year.
While the investigation into the loss of Air France flight AF447 has yet to reach any firm conclusions, the inquiry has highlighted evidence of airspeed information problems. This, in combination with the other incidents, has placed suspicion on the pitot tubes.
Alter is advising its members not to fly the A330 and A340 fleet unless at least two pitot tubes have been modified per aircraft.
"Alter deplores that, while waiting for the replacement of all the defective pitot tubes, management has not taken the decision to ground the A330 and A340s not yet equipped with new pitots, whose replacement is only due 'in the next few weeks'," says an Alter statement.
"So that a catastrophe does not happen again and while waiting for results of the various inquiries, Alter is inviting flight crew to respect the following union advice: Refuse all flights on A330/A340 aircraft that have not had at least two pitots modified."
Alter says ACARS messages from AF447 automatically transmitted during the final minutes of the flight consisted of warning and fault messages. It states that the first fault message was coded '34111506', pointing to a pitot-related problem during cruise.
"The pitots on this A330 had not been modified," says Alter. "There exists a real risk of loss of control of an Airbus arising from the loss of anemometric information - breakdown of two or three pitots - in the context of an extremely heavy crew workload resulting from this loss."