Question Author
mushroom:"there was a faulty sensor. this would not of itself cause loss of the aircraft; what did that was the crew were totally unprepared for the failure and didn't know how to work around it. " - not true, the crew did the correct thing multiple times but the plane believed it was stalling and overrode them, this was, as you say, due to a faulty sensor. Assuming it is otherwise correct, software is only as good as the information it is getting, thus you can never be certain the sensors are correct thus software should always be overridable.