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Old 3rd Jan 2013, 08:42
  #18 (permalink)  
HazelNuts39
 
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C* blend of pitch rate and g-load

Originally Posted by FCTM
When the PF performs sidestick inputs, a constant G-load maneuver is ordered, and the aircraft responds with a G-Load/Pitch rate.
Originally Posted by Stuck in an ATR
Actually, if you read the passage from the FCTM carefully,it says nothing about blending. The wy I read this, is that pilot commands constant "g". Aircraft's response is g-load/pitch rate (it always is, in any aircraft!). However, at low speed one needs higher pitch rate to obtain the same g, than at hi speed.
That is correct for the steady-state constant "g" that is eventually achieved. AIUI the 'blending' of G-Load and Pitch rate refers to the way the flight control computer controls the transition from the initial "1G" steady state to the commanded "x G" steady state.

The FCC initially orders a movement of the elevator. It monitors the response of the airplane and adjusts the elevator movement accordingly. The 'response of the airplane' is expressed in a 'feed back parameter' C* which is formed by adding the sensed pitch rate multiplied by a constant to the sensed G-Load. Thus the value of the constant determines the 'blend' between the pitch rate and G-Load terms that together form the feed back.
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