Specifications

• The one-way bearing in the autorotation hub may be loose.
26.2.5. Tail servo responds in one direction only
• Tail servo responds properly when tail swings one direction but tail servo fails to respond in
other direction.
• The gyro may be damaged.
26.2.6. Tail drifts as battery discharges
Tail holds fine at the beginning of a flight, but starts to drift as the battery discharges. This is
normal for a yaw rate gyro. Heading hold gyros do not have this problem.
26.2.7. Tail motor runs at low throttle
The heli tail runs even at low throttle when using a heading hold gyro and a tail motor. This is
normal. The heading hold gyro does not output zero throttle unless it receives a full left rudder
stick. This is why you need to hold full left rudder to initialize the tail ESC.
26.2.8. Tail servo creeps or does not recenter
Tail servo slowly moves in one direction (creeps) when heli is on the ground with heading hold
gyro. This is normal. Don't worry about it.
26.2.9. Tail servo travel is unequal
Tail servo travel is unequal on both sides of the neutral point with heading hold gyro. This is
normal. You should set the servo travel in the non-HH mode and the heading hold mode will
work automatically.
26.2.10. Tail motor has insufficient tail thrust
Helicopter has a tail motor, and has insufficient tail thrust to counter main rotor torque. Tail
prop may be mounted backwards. Examine the prop airfoil - the prop should be mounted so
the airfoil will gradually increase pitch as the air moves past the rotor.
26.2.11. Tail servo travel is not settable using Transmitter EPA with
heading hold gyro
This is correct. With a heading hold gyro, the transmitter EPA controls the pirouette rate. The
tail servo travel must be set using the LIMIT adjustment on the gyro. If the gyro does not have
this feature, then the tail servo travel cannot be set, and you must move the tail servo linkage
to a different servo horn hole to increase or decrease the linkage travel.
26.2.12. Tail servo moves in the wrong direction with a heading hold
gyro. Reversing the transmitter rudder channel has no effect.
The transmitter rudder channel reverse function does not change the servo rotation direction
with a heading hold gyro. It only changes the yaw direction command to the gyro.
The tail servo rotation direction can only be fixed by using the reverse switch on the gyro, or if
Troubleshooting Common Problems
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