The evening of May 31, 2009, was like any other in Rio de Janeiro. As the crew of an A330 prepared for departure, it would have been like any other flight home. A long stretch over the deep black of the Atlantic, dodging thunderstorms as they made their way back to Paris. Tragically, a few hours later the aircraft would enter a deep stall and fall into the ocean.

After a lengthy investigation, it was found that the pitot tubes which help detect the airspeed had momentarily frozen. This gave the crew conflicting and confusing information on the screens which ultimately led the speed to drop so low that the wings were not generating enough lift to keep them flying.

If anything positive came from this awful event it’s that it served as a wake-up to the industry to the dangers of unreliable airspeed and how it is handled by crews. It forced manufacturers and operators to review their procedures and improve training for pilots.

How the problem is dealt with very much depends on the aircraft type and how the airspeed is sensed and presented in the flight deck. As a result, when training on a new type of aircraft, it is important that we as pilots know exactly how the pitot-static systems works and what to do should they fail.