Thierry Dubois is a freelance writer specializing in helicopters, business aviation and aerospace technology. He earned a degree in fluid dynamics from an engineering school in Toulouse, France in the mid-1990s. At an unexpected crossroads, he found his first job in journalism. In 1997, he started working for French aerospace weekly Air &amp; Cosmos in Paris. This lasted until 2000, when he moved south to Lyons. He then became a freelancer, working for various aerospace publications and has been part of the AIN team since late 2000. In addition to writing about business aviation, Thierry shares responsibility for the rotorcraft section. He also is a regular on-site writer for AIN’s daily editions at international airshows such as the Paris, Farnborough, Dubai and Singapore shows, as well as at EBACE in Geneva.
In 2007, he won the Honeywell award for “Best systems or technology submission” at the Aerospace journalist of the year awards. In 2013, he won an Aerospace Media Award for the "Best Safety, Training &amp; Simulation Submission."
In other activities, Thierry moderates international conferences on aviation technology topics. Thierry is married and has three children, who seem to begin enjoying the mountains–as their parents do.

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Thierry Dubois

The <a href="http://www.ainonline.com/aviation-news/2012-07-09/french-release-final-report-air-france-447">final report on the crash of Air France Flight 447</a>&nbsp;is giving ergonomics specialists food for thought. One area of particular focus has been the stall warning, which the report says the crew ignored. BEA investigators have suggested several factors that might explain why the crew did not react to the alarm, despite its sounding more than 70 times as the Airbus A330-200 descended at up to 11,000 feet per minute, at angles of attack ranging between 35 and 45 degrees.


One explanation centers on the possibility that the crew might have thought the buffeting, aerodynamic noise and even an acceleration cue on the primary flight display were symptoms of overspeed. The report questions whether the crew even heard the alarm. When it sounded, the pilots were already highly stressed and perhaps so absorbed with the onslaught of visual information that their brains failed to process the aural cues, suggested Sébastien David, head of the investigation's human-factors group. Against this background, the BEA is recommending a dedicated visual stall warning. In the case of flight AF447, the speed tape had disappeared from the display and therefore could not indicate the stall.


Moreover, the report continues, the pilots received “very little [exposure] to stall situations” in their training, hence a lack of familiarization with the stall warning and the actions it should have triggered.


More generally, the BEA believes a better understanding of the overall physics of flight at high altitude would have helped the pilots. They would have recognized that pitch-up control inputs before the stall were robbing the airplane of its kinetic energy and thus could have “anticipated the rapid degradation of the situation.”


Had the crew identified the stall after the onset of buffeting, a “straightforward pitch-down input” on a sidestick would have taken the A330 back into its flight envelope, according to tests conducted jointly with Airbus, said investigator-in-charge Alain Bouillard.


The accident,&nbsp;on June 1, 2009,&nbsp;killed all 228 people on board as the aircraft plunged into the Atlantic Ocean while en route from Rio de Janeiro to Paris.

Air France 447 Probe Raises Questions about Stall Warning Ergonomics

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