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Old 18th Feb 2017, 20:00
  #21 (permalink)  
Chris Scott
 
Join Date: Jan 2008
Location: Blighty (Nth. Downs)
Age: 77
Posts: 2,107
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Quote from FE Hoppy:
"A good example is the Flap Fail/ Slat Fail procedure on the Ejets. Depending on the failed surface the optimum position of the non failed surface is as much to do with landing attitude as it is to do with stall speed.
Too nose high and the de-rotation eats up landing distance so the compromise is a slightly faster landing speed with a lower attitude on touch down."

With slats-only the possibility of tail strike certainly has to be taken into account when planning the standard FCOM increment pilots apply to the Vref (+25 kt, for example), due to the pitch-attitude on approach being much higher than normal. But with flaps-only the attitude is much lower than normal, because of the higher IAS (again, +25 would be typical). You and other posters imply that brakes cannot be used until nose-wheel touchdown. That doesn't necessarily apply to modern types, and I agree with GlenQuagmire: in my experience there is more than enough elevator authority on the A320, for example, to counter medium-autobrake and achieve a smooth nose-wheel touchdown, and that should apply at the higher touchdown IAS associated with partial absence of high-lift devices. (Must admit I never used the MAX setting on landing.)

Prior to nose-wheels touchdown, with reduced weight on the wheels despite the lift-dumpers/ground-spoilers, the anti-skid system should if necessary limit the intensity to whatever is achievable?
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