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Old 13th Jan 2014, 18:52
  #30 (permalink)  
keith williams
 
Join Date: Jan 2011
Location: England
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Anyway, an aircraft in flight only cares about moving through an air mass with sufficient speed ("airflow due to airspeed"), not whether that air mass itself is moving relative to the ground ("airflow due to wind").
Which is pretty much what I said earlier. An aircraft responds to the air flowing over it. It has no mean to distinguishing between airflow due to wind and airflow due to forward motion of the aircraft.

This entire area of discussion is based on using the atmosphere as the frame of reference, then calculating the speeds and forces relative to it. In effect we assume that the atmosphere is stationary and any airflow is purely the result of motion of the aircraft. To do this we reverse the direction of the wind and add its speed to the aircraft. But none of this means that the aircraft does not experience the wind. It simply means that we have simplified the situation by selecting that particular model. But it is still just a model.

If you don't like the kite analogy, consider an aircraft with a TAS that is exactly the same speed of the headwind. If it does not experience the wind it will not be required to generate any thrust or power to maintain the situation. Now just shut down the engine and we will see just how much the aircraft is experiencing the wind.

SSD, like many people you appear to be assuming that because you have been doing something for many years, this must mean that you understand all about it. This is a false assumption.
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