PPRuNe Forums - View Single Post - DO winglets have effect on Vref when landing?
Old 13th Apr 2014, 14:09
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HazelNuts39
 
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Minimum control speed and stall speed

Whereas the stall speed varies approximately as the square root of weight, the change of minimum control speed with weight is very small. The reason that it changes at all is the bank angle of 5 degrees allowed in the determination. So if someone says that at a particular weight the minimum control speed is less than the stall speed, he is comparing the stall speed at that weight to the minimum control speed established at a lesser weight and extrapolated to the actual weight.

Another aspect to consider is that the stall speed is determined with power off, whereas Vmc is determined with TOGA thrust on the operating engine(s). Since a component of the thrust contributes to the lift, it is in fact possible to demonstrate Vmc below the power-off stall speed.

Last edited by HazelNuts39; 13th Apr 2014 at 14:33.
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