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Old 5th May 2012, 14:28
  #406 (permalink)  
rudderrudderrat
 
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position relative feed back side sticks

Hi DozyWannabe,
If you can fly with a yoke you can fly with a side stick. If both approaches work with no significant impact on safety, there's no compelling reason to standardise on one.
The Airbus side stick system lacks the "position of the control surface feed back loop" to the pilot. We have no easy way to sense how much control surface deflection is required to satisfy our side stick input. It is very useful for an experienced crew to know.

Imagine replacing the steering wheel of your car with a side stick.
http://www.auto-ui.org/09/docs/p19-kienle.pdf
On page 21 it shows the results of various side stick control feed back loops. The only negative results are from the "spring centred force reflective" side stick (similar to Airbus s.s.). It's also interesting to note the perceived difference between experienced and non experienced drivers. (your observation in post #396)

Pilots really need to be alerted when their control surface is being deflected by an "unusually" large amount. During asymmetric flying, the deployed roll spoilers on the lower ECAM page attract one’s attention. With the aircraft in trim properly, they remain stowed. Since there is no "position relative side stick" on the Airbus (nor feed back for the side stick demand from the other pilot), we really need something similar to warn us that the elevator (or stab trim) is outside its normal range.

Last edited by rudderrudderrat; 5th May 2012 at 15:55. Reason: still can't spell
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