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Old 9th August 2012 | 08:38
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RetiredF4
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Response times of elevator and THS

PuraVidaTransport
So can someone explain why it takes so long to get control surfaces to give the actions requested by the pilot. As I see it, the pilot wanted the nose down for 17 seconds and got nothing more than 15 degree nose up then the other wanted FULL nose down for 7 seconds and the computers once again only gave him nose up elevator. Does this have something to do with the cumulative inputs? Can a set of bad inputs cause the airplane to not respond quickly as was needed in this case??
That question was asked before, and i hoped the final report would answer this quetion. Bottom line is, that you have to ask the automation logic, because the SS only orders a change of g. How much change was ordered with full ND SS? I dont know, there are tables with g values corresponding to respective SS deflection, but i dont know wether there are speed gains involved or wether the load factor protection could have played a role in this.
Load factor protection was the only protection left, and again, i dont know wether it has some speed dependent gains as well.

Maybe an overlay of the graph you mentioned with actual normal acceleration values would shed some light.

Last edited by RetiredF4; 9th August 2012 at 08:40.
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