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Old March 20th 09, 12:15 PM posted to rec.aviation.soaring
Bob Cook[_2_]
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Default aerodynamics of gliding

That would not be possible......only "momentary". You can't "keep"
"everything else" constant.

Yes, there would be a "momentary" increase in lift......but......

Glider would experience "acceleration", change in velocity, and or
direction. (Most likely glider would "nose up" (change in direction)
then "slow down" (change in velocity) finally resume steady flight with
greater drag giving steeper glide angle.

Once "stabilized" flight is resumed, vector analysis shows flaps do not
increase lift. Yes, the coefficient of lift has changed but not the
actual lift (other than a really, really tiny reduction due to new flgith
path)

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At 09:40 20 March 2009, The Real Doctor wrote:
On 20 Mar, 01:15, Bob Cook wrote:

If we draw vector force diagrams of two identical gliders, one with

flaps
extended, and the other with flaps retracted, we can easily see that
"lift" is essentially the same in both cases.


What happens if you extend the flaps on a glider while keeping
everything else (AoA, airspeed) constant?

Ian