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Old 2nd Dec 2000, 20:46
  #15 (permalink)  
Prof2MDA
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EchoTango,

No, I am afraid it is you that is incorrect here. My data is backed up by Boeing, NTSB engineers and 3 separate physicists who assisted me in analysis.

The amount of lift the wing is generating has a direct effect on the force. Consider the difference between contact with the ground under 1g, the wings supporting the exact weight of the aircraft. The force the gear has to absorb is based on the KE=1/2MV^2. Now, consider an object that is not being supported but is actually accelerating, such as a dropped object. The rate of change is only part of the equation, as the amount of force the gear will "feel" normally comes in two parts. Part 1 stops the vertical motion, part 2 the lift is removed and the gear feels the weight of the aircraft due to the normal acceleration of gravity (as you feel on your rear end right now as you sit reading this).

However, the wings are never going to be lifting exactly the weight of the aircraft (and I'm rolling TDL into the weight) during the landing phase due to transients, but if the trend is a normal flare the lift is actually slightly greater than the weight so the aircraft is accelerating upwards (slowing it's vertical speed) and the g will read a bit above 1. If the reverse is occuring the aircraft is accelerating downwards at some rate, which means the gear has to absorb that additional component.

Of course, we must also factor in the pitch transients, but to make that work in your favor with decreasing pitch prior to touchdown it requires precise timing before the above factors outweight it, and of course if you don't time it precisely the recovery is not possible due again to the pitch transient in the reverse direction.