Futaba GY501 - Manual (Page 27)

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B
EFORE
U
SE
In the AVCS mode, the gyro automatically trims the rudder so that
linkage changes cannot be verified. Initially, the GY501 trims the
rudder by flying in the Normal mode to take the rudder linkage
neutral position. This centers the linkage. At this time, this rudder
neutral reference point is read to the GY501.
Giving the gyro the rudder neutral reference signal and performing
tail operation by referring to this signal in the AVCS mode in this
way is how the AVCS system differs from the conventional system.