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Old 29th Nov 2012, 14:23
  #29 (permalink)  
Dg800
 
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Flaps will increase coefficient of lift and wing area so it's opposite what you want. So the airplane will feel any gust and will be even more difficult to control. So that's why in gliders we land with landing flaps in normal days and +2 in windy days.
What you're saying there is only half true, actually. Bigger planes do indeed have lift augmentation devices that increase both the camber and the surface area of the wing, thus a higher flap setting will really give you a larger surface area and so a lower wing loading, which makes the plane more susceptible to turbulence. Vice-versa a lower than full flap setting will give you a higher wing loading which makes it somewhat more manageable in severe turbulence, also because of the small increase in speed, which gives you higher kinetic energy, a smaller crab angle and increased control authority, as already mentioned in previous posts.
On gliders you only change the camber and hence the lift coefficient, the surface and the corresponding wing loading does not change. Ideally with severe turbulence you should retain your water ballast (=higher wing loading) until you've landed, this is however discouraged if not outright forbidden in most glider's POH for structural reasons, so you just set the flaps to "full minus 1 stop" for the increased speed and aileron authority.

Ciao,

Dg800

Last edited by Dg800; 29th Nov 2012 at 14:25.
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