PPRuNe Forums - View Single Post - Effect of CP on aircraft pitch attitude
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Old 15th Feb 2017, 22:41
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FCeng84
 
Join Date: Feb 2009
Location: Seattle
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Dumping lift is the name of the game

MFS - I agree completely. My point about landing at a higher attitude is that brake effectiveness is directly related to dumping lift so that there is more weight on the wheels to make use of braking friction. As you state, landing at higher pitch attitude means landing slower. This provides runway length benefit in two ways. First, as you mention, slower to begin with is better. Second, slower to begin with also means more weight on the gear once derotated and thus greater brake effectiveness. As a side note, ground spoilers used as speed brakes result in a minor increase in drag while their main benefit is dumping lift to make the wheel brakes more effective.

I am still puzzled by the notion that landing as slow as permitted by touchdown pitch up to tail strike limits is not the optimal for using the minimum amount of pavement to stop. I have never seen any manuals suggesting that landing faster will require less runway!
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