This property sets the amount of lift for a Wing object as it is rotated.
SetFlapLift provides lift dependent on what the angle of the flap is, and so can be the complete opposite direction of the SetWingLift setting. This basically allows you to set a component that is always supplied as vertical lift for the plane so that if your flaps are set very sharp you will not lose all your vertical lift that you may have had. For example, if you made a airbrake flap, it would still have the lift to keep you up in air even if the flap is moved to a vertical or upside down position, but allow the flap lift to slow your forward motion down, etc.
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