This is used to modify the effect of a key or button on the pitch, rotation, etc. If set to 1, it resets the throttle to zero after user input is removed. If this property is not specified (or set to 0, the default), the last key pressed continues to be used even after the key is lifted.
In other words, if this is set to 1, you need to keep holding down a key to keep moving. With 0, you will go forward, say, with one keypress and continue to go forward until some other key is pressed. See SetMinRotation for more information.
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