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Old 11th May 2009, 01:02
  #445 (permalink)  
IFMU
 
Join Date: Mar 2005
Location: Poplar Grove, IL, USA
Posts: 1,102
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Dave,

I learned something that I didn't know- the slight increase in power when accellerating in ground effect. I never would have thought it true, either academically or from flight experience in little helos. So, thanks for the chart.

Regarding the stripping of lift, I still have a hard time with that one. When will the propeller be pulling lots of air? At high speed. Will the rotor downwash even be hitting the propeller? At Sikorsky's claimed 250 kts, that is a lot of air zipping under the rotor. If the prop did anything bad to the lift, I wonder if it would be measurable.

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