Most helis need the tail rotor servo to pull the tail rotor pushrod forward for right rudder.
Move the rudder stick to the right, the servo should pull the pushrod forward. If it goes the other way, reverse the rudder setting in the TRANSMITTER.
Next, pick up the heli, turn the nose to the LEFT while watching the servo arm. It needs to move to pull the pushrod forward, to the nose of the heli. If it goes the other way, reverse the setting at the GYRO with the NOR/REV switch.
BOTH settings have to be correct or you'll never get off the ground in one piece.
And yes, somewhere out there on RR (use the search function), I've written a ton of "How to make the 401" behave posts.
Also, when the gyro completes its power-on initialization, the red LED needs to ON, not blinking, flashing, or pulsing. If it's not ON solid, then you didn't initialize the 401 in Heading Hold mode, and it will be unhappy.
When operating in Heading Hold mode, NEVER use rudder trim. And the RUDDER trim setting in ALL transmitter flight modes must be identical. The gyro learns rudder neutral position during power-up initialization. If you change the neutral point after that happens (using either rudder trim, or your rudder trims in the flight modes are different), you'll confuse the gyro because what it learned for neutral has changed. I always disabled the rudder trim on my TX when I used the 401 to avoid accidentally bumping it.
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