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Old 8th May 2013, 21:36
  #540 (permalink)  
henra
 
Join Date: May 2010
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Originally Posted by FCeng84
The forces felt by an object within an aircraft are those generated by aerodynamic forces and thrust, not gravity. The greatest component along the X-axis is thrust. Thrust is greatest when at low airspeed (engine thrust decreases with speed.
hmmm, almost.
The Forces felt by an object within an aircraft are those generated by Thrust, Aerodanymic Forces and Gravity.
Balance of forces wrt longitudinal axis of the aircraft:
Thrust(airspeed) - Drag(airspeed) - Gravitational Force x sin(Alpha) = Mass x Longitudinal acceleration.
or
SET(airspeed) - Gravitational Force x sin(Alpha) = Mass x Longitudinal acceleration.
So you can trade between Gravtitational Force as a function of AoA and longitudinal acceleration assuming same airspeed.
For the load it will largely 'feel' the same. Largely because the force component vertical to the floor will change with the cosine of the AoA. On the other hand when accelerating longitudinally airspeed will obviously change over time so this is only the momentary effect.

Last edited by henra; 8th May 2013 at 21:40.
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