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Old February 15th 11, 09:41 AM
Ronald Locke Ronald Locke is offline
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First recorded activity by AviationBanter: Jul 2010
Posts: 4
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Quote:
Originally Posted by Andy[_10_] View Post
On Feb 14, 1:15*pm, Ronald Locke Ronald.Locke.
wrote:

Given a Blanik at, say 28 to 1 no brake deployed, would around 8 to 1
full brake and say around 15 to one half brake sound about right?

Thanks in advance.

Ronald Locke


If they're terminal velocity brakes then 0:1 (straight down) is
possible without exceeding Vne. Form drag is highly speed-dependent so
speed affects the answer a lot. The size of the brakes also matters so
it is unlikely you will get a consistent number across multiple types.
You'd also need to define "half brake" - halfway out, half the
additional drag, half the difference in glide angle, one brake in and
one out?

Given all the variables I suspect it's possible to fly a Blanik to
achieve the glide angles you describe. The tricky calculation would be
to estimate the best L with dive brakes deployed. I'm trying to
figure out the circumstances under which someone would try to achieve
best L with the brakes out rather than just retracting the brakes.

9B
My query is simply related to the different approach angles on final glide to the aiming point during final approach for landing. Obviously different gliders will have different glide ratios for full brake and half brake approaches. Hope this explanation clears up any misunderstanding.