There was no indication that the air speed indicators were defective, they were operating outside the design limits, limits that apppear to be imposed by the laws of physics. Some of the design decisions may have contributed to this tragedy, but the decisions do not seem to have been made to cut corners, or without sufficient deliberation.
Had they made different decisions, it might have averted this disaster, but caused others, perhaps worse. I remember in my undergraduate control systems course, the textbook authors described a decision to make an aircraft control system less responsive to pilot input, knowing that it might ocassionally lead to an avoidable accident. The reasoning was that the less responsive control would actually prevent many more accidents than the more responsive control system would prevent.
The Airbus has its drawbacks, but it appears to be a perfectly airworthy airframe with an excellent safety record.
I didn’t say the A/S indicators were defective. The pitot tubes which provide input to the A/S had known problems for the model that was installed and Air France knew about it beforehand but were stalling on the changeout. I also didn’t fault the airframe. Regardless, the incident was recoverable but for bad piloting!
JC