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View Full Version : Stalling. How many G's?



DKoor
06-14-2008, 12:01 AM
I wonder how many G's would be influencing pilot's body in flat stall... for instance, when in flat stall, P-39 does full circle in less than 2 seconds on speeds 150-160kph.
Judging freely from that, it must be quite unpleasant experience.

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DKoor
06-14-2008, 12:01 AM
I wonder how many G's would be influencing pilot's body in flat stall... for instance, when in flat stall, P-39 does full circle in less than 2 seconds on speeds 150-160kph.
Judging freely from that, it must be quite unpleasant experience.

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

K_Freddie
06-14-2008, 12:10 AM
I would imagine that it depends on what speed you're initially travelling at, and how violent the spin entry is. Once the spin 'stabilises', the g-forces should be close to, or just over 1.

Centrifugal G-Forces would depend how far the cpit is from the centre of the spin.
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TinyTim
06-14-2008, 12:45 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by K_Freddie:
Centrifugal G-Forces would depend how far the cpit is from the centre of the spin.
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif </div></BLOCKQUOTE>

Exactly. In a P-39 pit is very close to axis of rotation, so g-forces (from rotation) should be low. Centripetal acceleration goes linear with radius (and square with frequency).

It's a whole another story for a B-25 tail gunner! Fortunately these enter flat spins rarely http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif.