On June 1, 2009, Air France flight 447 from Rio de Janeiro (Brazil) to Paris (France) suddenly entered an aerodynamic stall and crashed into the Atlantic Ocean, killing all 228 passengers and crew onboard. Although the initial reports on the possible causes of the disaster evolved around the malfunction of the plane’s pitot tubes, the investigation concluded that the main reason for the tragedy was pilot’s mistake.

The author of this article, Tom Dieusaert, is a Belgian journalist and author of “Computer Crashes: when airplane systems fail” (ISBN 978-987-24843-4-7) based on the AF447 accident.

It is often debated whether the accident of Flight AF447 from Rio to Paris was partly a consequence of the Airbus flight controls. No linkage between sidesticks, lack of feedback, a deceptive Flight Director, auto-trim and a flawed stall alarm. Two Air France Captains share their opinions. One of them is Gérard Arnoux, now retired, who for many years flew Airbus 320 for Air France and is now a technical advisor in the criminal court case. The other captain, who prefers to remain anonymous, flew Airbus 320 aircraft for many years and is now currently commanding a B777.

The Boeing 777 is known as the competitor of the A330 and is also a fly-by-wire aircraft. What’s the difference?  

Air France B777 Captain: On the B777 we have fly-by-wire flight controls but Boeing philosophy is different from Airbus. On a Boeing you see the input of the other pilot on the flight controls, as you see the autothrottle inputs at a glance. On Airbus you must search for information. For the throttles you have to “read” engines N1 (rotation speed in %) like you would read a digital clock.

Having a yoke with physical feedback is quite different than having a joystick.

Air France B777 Captain: A Boeing-777 will always give you a physical feedback of your pilot action and physical evidences when your pilot actions are wrong. On Airbus the G-load piloting law erases a lot of that physical feeling.

The G-load piloting law is why the Airbus is so easy to pilot when everything goes right, because the aircraft is always in trim, and you realize it’s like you would pilot through an autopilot: just look at flight director and make corrections through small inputs and that’s enough. I have flown the A320-family and it’s very easy to fly once you have understood that your inputs, with your wrist on the joystick, must be very accurate and minimal. The less you touch, the better it works. When you are very gentle and accurate on the stick, it’s a pleasure to see it flies alone. You can’t do that on Boeing 777.

Until something goes wrong. Like unreliable speed readings, for instance.

Air France B777 Captain: You must know that training on speed failure in a simulator was very rare and during my 25 years practice on French airlines − before 2009 − I must have been trained maximum 3 times in a simulator for this situation, while we were having at least 2 engine failures to deal with at every simulator session.

I do not know why speed failure was not trained. This kind of failure can be very stressing when at the same time you have overspeed warning and low speed warning, even stickshaker… The basic principle is to do nothing, just keep your thrust and attitude parameters of the aircraft. In the early years of the A320 we still had an incidence-meter (angle of attack meter, not installed on the A330) but still it is not easy and to rely on instruments, when real and false alarms are raised together.