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Old 6th Aug 2012, 19:50
  #600 (permalink)  
RetiredF4
 
Join Date: Jun 2009
Location: Germany
Age: 71
Posts: 776
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Clandestino
This difference didn't prevent the pilots of conventionally equipped aeroplanes from pulling into stall or Airbus pilots successfully negotiating the loss of airspeed information.
What a silly straw argument.
Antiskid does not prevent runway excursions completely, therefore those systems are not useful?

Car accidents during braking actions involve more cars with antiskid systems in Europe than cars without such a system. Naturally because most cars on European roads are equipped with such a system.

Clandestino (my bolding)
However, your claim, which many a PPRuNer would readily agree with, is indeed useful as it reveals not what is wrong with Airbus controls interface but what potentially dangerous habit many a pilot has acquired: checking just the controls movement to see what the aeroplane is doing. Now this might be newsworthy to some: control or thrust levers positions are only demands, which absolutely has to be crosschecked against the instruments to see what effect they have on the aeroplane! That you need to have closed loop feedback via instruments is something trained from first second of instrument flying and is as true on C-172 under the hood as it is in A380 flying through clouds.
You name it absolutely correct, and what do you want to tell us?
How is your closed loop feedback ------ demand by pilot via control / thrust levers position versus effect crosschecked via instruments ------ functioning? For the PF it is functioning, as he is the one who is initiating the demand (assumed that the demand is not altered by the automation), the PNF might lack the demand (control position) and has to rely on the effect (instruments) only. The closed loop system is not available to him.

That didn´t go unnoticed during the analysis of BEA and is posted in their final report.

BEA FR 2.1.2.3 Control of the flight path
It would also seem unlikely that the PNF could have determined the PF’s flight path stabilisation targets. It is worth noting that the inputs applied to a sidestick by one pilot cannot be observed easily by the other one and that the conditions of a night flight in IMC make it more difficult to monitor aeroplane attitudes (pitch attitude in particular).

Last edited by RetiredF4; 6th Aug 2012 at 22:51. Reason: Correction on headsup from Clandestino PF to PNF
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