[ConservativeWarrior]

The graphic in post 10 shows 4 minutes. Any fall from 35,000 feet takes time.

That's true, but even if it took 4 minutes from first alarm to impact, that doesn't mean they had 4 minutes to recover. There's a point where things are too far gone to correct, no matter how much altitude you have. The degree to which that was true in this case is unclear it seems.

What I don't understand is why there aren't backup pitot tubes on airliners, concealed and out of the icing conditions until needed. Sort of like the RATs that pop out of the fuselage to supply emergency power generation. Why not have one or more pitot tubes concealed from the elements that can be deployed when the others have failed?

[fireman15]

The pitot tubes are heated to prevent them from icing. I am also sure there is redundancy in the system and procedures already in place to prevent or correct instrument failure. Don’t assume that those of us discussing this are “smarter” than the aircraft designers. Although this plane is the result of a partnership between a government and industry so that in itself could be a recipe for trouble.

[driftdiver]

“There’s a point where things are too far gone to correct, no matter how much altitude you have.”

The only point is when there isn’t enough altitude or when the plane loses a control surface. Depending on the design of the airplane there are very few stall conditions which are not recoverable given altitude and a working airplane.

There are backups on most airplanes, these generate their own risk. In my complete amateur opinion the engineering of the Airbus is not all that great in a number of areas.