Futaba GY520 - Manual (Page 29)

29
A
DJUSTMENTS
D
URING THE
T
EST
F
LIGHT
The Tail Rotor AFR or D/R function within the transmitter is used
to adjust the pirouette rate of the helicopter. For example at 100%
D/R, with the gyro set to F3C mode, the helicopter will achieve a
450 deg/sec pirouette rate. If you would like the model to pirouette
faster, then increase the AFR or D/R. If you would like the model
to pirouette slower, then decrease the AFR or D/R.
The gain should be raised until the tail begins to oscillate quickly
(also called Tail Wag). Once this point has been achieved, reduce
the gain by a couple of percent and test fl y the model again. Check
and set the gain for each fl ight mode. Typically the gain will be
lower for the Idle up 1 and Idle up 2 fl ight modes due to the higher
head speed being used. The gain for the Hold condition can also be
much higher than other fl ight modes since the head speed is lower
and the engine vibration is minimized.
The tail rotor ratio, tail rotor pitch range and tail blade length play
a large part in achieving optimum tail rotor performance. The gain
value can vary drastically from model to model and the exact value
should not play a part in the evaluation of the gyro’s performance.
How the gyro operates during fl ight is the only concern of ours.
WARNING!
Always make small (1%) adjustments to the tail rotor D/R or
EPA once the value exceeds 100%. Over 100%, it is possible
to exceed the sensor’s Angular Velocity Sensing Range
(+/- 800° per second). The gyro will then no longer control
the pirouette rate or consistency. The pirouette rate will be
extremely fast.
If you experiment with the ultra-fast pirouette rate, make
sure that your fl ight battery and fuel tank are secure. Also be
certain that your model’s tail rotor drive train is up to the task.
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