On July 6 of 2013, Asiana Airlines Flight 214 crashed on final approach to San Francisco International Airport, resulting in over 180 injuries, 3 fatalities, and the loss of the aircraft. While the NTSB report on this accident is not yet out, there are several things that seem to be pretty clear:There is a long, long history of Airbus flight crews getting confused by the electronic system design. Each time, the accident report clears Airbus because the "systems were functioning properly". Each time, there's another next time, and people keep dying.
–The flight crew believed that airspeed was being controlled by the autothrottle system, a device somewhat analogous to the cruise control of an automobile
–In actuality, the airspeed was not being controlled by the autothrottles
–The airspeed fell below the appropriate value, and the airplane dipped below the proper glidepath and mushed into the seawall
It is not yet totally clear why the autothrottle system was not controlling the airspeed when the captain and first officer believed that it was doing so. It is possible that the autothrottle mechanism failed, even that it failed in such a way that its failure was not annunciated. It is possible that an autothrottle disconnect button (one on each power level) was inadvertently pressed and the disconnection not noticed. But what seems likely in the opinion of several knowledgeable observers is that the captain and FO selected a combination of control settings that they believed would cause the autothrottle to take control–but that this setting was in fact not one that would cause autothrottle activation…in other words, that the model of aircraft systems in the minds of the flight crew was different from the actual design model of the autothrottle and its related systems.
My take is that the systems are "Working As Designed (WAD)" but are repeatedly confusing the pilots. The answer to this is not "better training", it's "simplify the damned system".
I'm sure that there are people reading this who will think that I'm being unfair to Airbus. I'm also quite sure that pilot confusion will kill more Airbus passengers.