Negative G's and Stall Speed
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Negative G's and Stall Speed
What affect does negative G's have on stall speed in terms of load factor?
As negative g's is considered a negative load factor how do you work out the new Vs.
Example:
Vs (New) = Vs x √LF
Vs (New) = 50 x √-1
However you cant square root a negative number.
As negative g's is considered a negative load factor how do you work out the new Vs.
Example:
Vs (New) = Vs x √LF
Vs (New) = 50 x √-1
However you cant square root a negative number.
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The Vs of the wing with a negative load factor of 1?
Determined by experimentation - don't do it on finals.
Determined by experimentation - don't do it on finals.
If your aircraft has symmetrical wing and tailplane sections, then the stall speed at -1g will be the same as at +1g. However...…………… in reality, nearly every aircraft has wing and tail sections that are optimised for +ve g loads. This means that the CLmax in -ve g conditions will be lower than that for +ve g, and thus the stall speed under -ve g will be increased. To work out by how much, you need to know both the CLmax figures.
The V-n diagram for a particular aircraft will give you the information. In the example here you can see at minus one "g" the stall speed is about 130 knots versus 100 knots at plus one "g".