At least one of them realized it, but not the one flying. From http://www.bea.aero/en/enquetes/flight.af.447/transcript29ju... :

"At 2h10.16 seconds, the pilot in the left seat, the pilot not flying, says “we have lost the speeds” then “alternate law”"

Okay. This is how the cockpit apparently looks: http://www.pbase.com/image/47231836

Where are you going to stick the indicator light so that it's impossible to ignore it or mistake it for something else.

Some ideas:

Illuminate the pilot's footwells with a bright red light. There is normally no illumination there at all, plus it takes up a fairly large percentage of their viewable area when looking at their screens.

Or, change the background colors of all the screens from black to red. That might harm usability too much though. Maybe change all the other switch backlighting over to red. Or change the cabin overhead lighting over to red.

To the greatest extent possible, the entire environment and interface needs to communicate the modal shift. And pilots would need to train on this shift constantly so that recognition, and the appropriate shift in thinking, would happen habitually.

> Illuminate the pilot's footwells with a bright red light

Might interfere with normal/night vision.

Make it a loud, repeated aural indication. Oh wait, the stall warning was just that and got completely ignored...

I think we've discovered the most difficult UX design task on earth.

You know that Don Norman's insights come, in large part, from investigating nuclear reactor controls (Three Mile Island) and air crash investigations.

I am no aviation expert, but according to other posts here the stall warning may have been ignored because Bonin didn't register that they were in alternate law. If they weren't in alternate law, the plane would have automatically limited the amount to which he could pull back.

The most obvious solution to me, if all of that information is accurate, is that there should be a distinct audio stall warning for alternate law.

Instead of the plane saying "Stall... Stall... Stall... " when in alternate law it should probably say "Stall... alternate law... Stall.. alternate law...". Doesn't guarantee you the pilot will listen, but it seems like it is pertinent enough information to push it front and center along with the stall warning.

It seems like that when analyzing this accident. If you analyze another, there may be 2 or 3 other things that would seem "pertinent enough information to push it front and center". And yet more for a 3rd accident.

The problem is that making something more noticeable automatically makes everything else less noticeable...

The two things that seem to big huge contributors to the crash are that the pilots may not have realized they were in alternate law soon enough & one or both pilots did not realize that one of them was holing the stick back stalling the plane.Both of these seem like glaring UX & training issues.

It does not appear that it's very clear when the plane goes into alternate law & it does not appear they receive much training on how to fly in alternate law. Even if they do receive training, you probably do not want your most novice pilot handling the controls in alternate law. Additionally the averaging of the inputs seems to be the most obtuse way for pilots to realize mismatched inputs.

I agree with you in general that it is a balancing act, but if you're going to have a modal interface (normal law, alternate law) and the plane's flight controls are going to perform differently depending upon that mode, an indicator of which mode you're in is immensely important in any situation.

Typically there are two lights, master caution and master warning, that indicate a problem. From there, the details can be read on another screen. Additionally, there are voice alarms for critical events, like "Traffic! Climb now!" or "Fire! right engine!".

I don't know how an Airbus notifies the crew of the switch to alternate law, but I'm willing to bet that the master caution light comes on.