AF447

[Hyperveloce]

Well, if you get stall alarms at a flight level of 350 and if you see -50 kts of speed trend (trend over 10 seconds) on your PFD, isn't it a powerfull invitation to think quick, given your thin margin ? (probably <50 kts at FL350 ?). No need to panic of course, but you have to take this decision just after being rained down with multiple ECAM alerts, aural and visual alerts, and after having lost most of your flight protections. Maybe you had a little time to think about these multiple signals, to try to understand all these confusing signals displayed on the ECAM and the PFDs, then a new problem arises, you hear that your plane is stalling. No need to panic, but a clear & quick analyzis in a high workload & confusing situation ? The misleading signals: the stall warnings themselves, the airspeeds, the airspeed trends, the ECAM warning about "risks of undue stall warnings" and the SOPs urging you to take stall warnings into account (and to disreguard the ECAM warnings).
Sorry but I know how I feel when my PC goes haywire, produces strange & conflicting signals, and when my troubleshooting book or service is of no help. I how it can be frustrating, although I have all my time to comprehend between two coffees, in a flat world. I can't figure out how I would be, if I had only tens of seconds to solve a very confusing problem, with a plane to handfly in the same time with no visibility, in the night, buffeted in a tropical thunderstorm. I guess I would really be tempted to reboot the failed automation, but I am not a pilot.
All I know are past incidents, and past incidents show that some pilots are taking the stall alarms (and some other flight parameters) seriously. And some other incidents show attempts to reboot the PRIM/SEC inflight to regain a normal law. I don't know if you have the time to think, but in certain situations, you don't even have the time to send a MAYDAY.
Jeff
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PS) Are there formulae or tables to compute the time needed to reach Mach 0.85 and Mach 0.90 starting from FL350, Mach 0.80, according to several descent angles (1°,2°,3°...) and different thrust levels (N1=0.85, 0.90, 0.95, Max) ? is it possible to compute the same thing but with a banking angle ?
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