Setting up the Belt CP
With the motor disconnected by removing the three large wires at the bullet connectors, turn on the radio and the helicopter and pull the idle up mode switch on left top of the radio towards you. You must ensure this switch is moved back before reconnecting the motor. Move the collective to the center. Adjust the linkages from the servos to the swashplate to ensure that the linkages meet the servo horns and bellcranks at right angles. Adjust the linkages from the bellcranks to the swashplate to ensure that the washout arms are horizontal (level with each other) and the swashplate appears level (perpendicular to the main mast).
There are a number of points that are worth checking to get best tail control.
The tail rotor blades should come up towards the front of the helicopter when the main rotor is turned clockwise. If not, the tail belt needs to be twisted in the opposite direction. The tail rotor blades should be turning thicker edge first.
It gives maximum useful tail blade pitch if the pitch control linkage for the tail blades is on the leading edge of the blade.
Check that pushing the rudder control right increases the pitch of the tail blades, and pushing the rudder control left decreases the pitch; if not, reverse the rudder channel on the transmitter's front panel.
Hold the helicopter by the tail boom, and rest a finger on the tail servo horn, apply right rudder and remember which direction the servo moves (as it moves against your finger). Turn the helicopter smartly counterclockwise (nose to the left) and confirm that the servo moves in the same direction it did when you applied right rudder. If not, the gyro needs to be reversed (either by turning it upside down, or flicking a reversing switch on the gyro); do this and confirm the change is correct.
If you have a heading hold mode gyro, switch to heading hold mode and confirm that when the rudder trim is central, the tail servo has no tendency to creep. If it does, apply sufficient trim to stop the creeping. (You may need to recentralize the trim every time you switch the helicopter on.)
Push the idle up switch back to its normal position, turn off the helicopter and the radio, and reconnect the bullet connectors. Switch everything back on again for flight testing!
Switch the gyro to rate mode and hover the aircraft (you might want to get someone more experienced to do this for you). Note the direction and amount of any rudder you have to hold to maintain the helicopter's heading. Land the helicopter and apply the rudder you were holding to see how much tail blade pitch it applies. Move the tail servo up or down the boom to apply this amount of tail pitch, and then repeat the process until the helicopter maintains heading in the hover with minimal rudder applied.
You can now switch the gyro to heading hold mode, and it should maintain the helicopter's heading with minimal pilot input.
This is for the stock receiver:
- 1. Top rear servo (to swashplate left connection).
- 2. Front servo (to swashplate front connection).
- 3. ESC (brown to bottom of receiver).
- 4. Gyro - (to tail servo).
- 5. Gyro gain (single wire plug), if needed.
- 6. Rear lower servo (to swashplate right connection).
- B. Not used (likely carries 7th servo channel, if transmitted).
All servo wires should be "white facing you".
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