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Old 4th Mar 2003, 04:00
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Lefthanded_Rock_Thrower
 
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On the live engine side the amount of drag introduced by application of flap is greater than the amount introduced on the dead engine side ( the wing with the live engine has greater dynamic airflow ).

So infact is increasing control ability, by attempting to reduce the turning force produced by the asymmetric thrust.

The angle\rate of climb are effected by the excess thrust\power, when flap is introduced, more power is required for the airspeed not to decay.


VMCA is calculated is by the worst possible scenario, ie:

MTOW
Flap to T\O ( so retract flap, increase performance and decrease control ability )
Gear Up
live Eng to full pwr
Aft C of G ( rudder less effective )
Sea Level, critical engine failed
Failed Engine wind milling

for those of us that fly non airline type aeroplanes, VMCA is more of a rule of thumb as opposed to a law, for example in a Cessna\Piper Twins VYSE reduces 1 knot for every 1000 ft of altitude.

Last edited by Lefthanded_Rock_Thrower; 4th Mar 2003 at 04:10.
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