Re: "Swiss cheese" theory - lots of holes have to line up
The pilots *didn't* initially know they had a pitot problem.
Listen to the CVR. THey were discussing an airspeed problem. Now they might not have realised that this was down to a frozen pitot, but they knew there was an airspeed problem. The procedure for that situation is to set cruise power and fly straight-and-level for 60 seconds. That would have fixed the issue - but they didn't follow procedure.
Hope this helps, and that you don't mind the clarification.
I never mind any clarification, although in this case, I don't believe this is such; despite the additional lead-up events that you have outlined, the reason AF447 went down is that PNF couldn't keep his hands off the controls. If he'd had his hands in his lap, the aircraft would not have crashed.
Vic.
Biting the hand that feeds IT
