Submission + - Air France, Airbus guilty of corporate manslaughter in 2009 Air France 447 crash (bbc.com)
UnknowingFool writes: The Paris Appeals Court found that both Air France and Airbus were "solely and entirely responsible" for the crash of Air France 447 over Atlantic Ocean which killed 228 people on June 1, 2009. The court overturned a lower court's April 2023 ruling which had cleared both companies. Both companies were fined the maximum of €225,000. While both companies blamed the cause of the accident on pilot error, prosecutors contend that poor training and failing to fix an known flaw led to the accident. In the accident analysis identified a root cause of the accident was pitot tubes which iced up during certain flying conditions. That icing caused erratic air speed readings fluctuating between low to supersonic within seconds of each other. Those conflicting readings led to a chain of confusing errors and warnings from the flight system including a stall warning. The plane was stalling however the flying pilot's (PF) attempted to climb out of a stall by pulling back actually caused the plane to stall into the ocean.
While not in the official report, a contributing factor noted by experts is the design of Airbus cockpits. One issue is the electronic fly-by-wire controls where the physical position of certain controls like the throttle does not match the input in the system. In this case, the autopilot had lowered the thrust output during flight, but it could not move the throttle position. The throttle position appeared that plane had more thrust than it did. In the Airbus cockpit, joysticks are used instead of a control yoke. The joysticks are symmetric in the layout of the cockpit in that the pilot on the left has the joystick on the left and the pilot on the right has their joystick on the right. The joysticks are also not linked to provide feedback to each other. The other pilot (pilot in command or PIC) could not know the PF was trying to climb unless he was looking directly at the PF's hands. The PIC realized the error too late to overcome the stall.
As for responsibility, Airbus had identified an icing problem on their Airbus 320 model planes and recommended those pitot tube be replaced as early as September 2007. Air France 447 was an Airbus 330, and Air France delayed replacing the pitot tubes until further recommendations. However, Air France themselves recorded had nine incidents between May 2008 and March 2009 on Airbus 330/340 planes where the pitot tubes failed due to icing conditions. Air France found six unreported incidents after the AF447 crash.
While the cockpit situation was confusing, crash investigators faulted the pilots for failing to follow procedures which would have been to first re-establish controls after the autopilot turned off. After the accident, pilot training now includes scenarios like AF447 where there is conflicting warnings. Also there was more emphasis placed on manually flying instead of relying on the autopilot.
While not in the official report, a contributing factor noted by experts is the design of Airbus cockpits. One issue is the electronic fly-by-wire controls where the physical position of certain controls like the throttle does not match the input in the system. In this case, the autopilot had lowered the thrust output during flight, but it could not move the throttle position. The throttle position appeared that plane had more thrust than it did. In the Airbus cockpit, joysticks are used instead of a control yoke. The joysticks are symmetric in the layout of the cockpit in that the pilot on the left has the joystick on the left and the pilot on the right has their joystick on the right. The joysticks are also not linked to provide feedback to each other. The other pilot (pilot in command or PIC) could not know the PF was trying to climb unless he was looking directly at the PF's hands. The PIC realized the error too late to overcome the stall.
As for responsibility, Airbus had identified an icing problem on their Airbus 320 model planes and recommended those pitot tube be replaced as early as September 2007. Air France 447 was an Airbus 330, and Air France delayed replacing the pitot tubes until further recommendations. However, Air France themselves recorded had nine incidents between May 2008 and March 2009 on Airbus 330/340 planes where the pitot tubes failed due to icing conditions. Air France found six unreported incidents after the AF447 crash.
While the cockpit situation was confusing, crash investigators faulted the pilots for failing to follow procedures which would have been to first re-establish controls after the autopilot turned off. After the accident, pilot training now includes scenarios like AF447 where there is conflicting warnings. Also there was more emphasis placed on manually flying instead of relying on the autopilot.
