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Old 11th Mar 2010, 03:17
  #29 (permalink)  
Intruder
 
Join Date: May 2000
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While it may work on a C150 because lighties are so speed-stable, it absolutely DOES NOT work on a jet on final, the most critical time of the flight where changes are required almost instantly.

Low-time pilots should not be taught to control the aeroplane via the secondary effects of controls, if for no other reason that when they fly something bigger, the technique doesn't work. While they are coupling effects so that the nose may come up when the thrust is increased, the primary method of changing the speed must be with the throttles (or speedbrake). Likewise, flight path change must be made with the elevator. Any speed changes are then sorted by changing thrust.
Sorry, but it's not that simple.

Both the A-6 Intruder and the 747 were/are relatively speed-stable in the landing configuration. In both airplanes, thrust is primarily used to control rate of descent, and pitch trim is used to control airspeed.

While all the performance inputs and parameters are interrelated, there is a primary or leading control input for change of each parameter. To attempt to control speed PRIMARILY with thrust in the landing configuration in either airplane will likely result in a very unstable approach.

This discussion could expand to roll/yaw response for turning in different airplanes, but that would even further complexify the conversation...
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