rates facilities work together so that setting the rudder ATV to 80% in both directions and also setting a
rudder rate of 60% will give a total rudder throw of 0.8 x 0.6 = 0.48 = 48%
100%
20%
40%
60%
80%
200
400
600
800
1000
1200
1400
1600
Rotation rate (Deg./s)
Rudder signal (as % of standard 1 to 2ms deviation)
Figure 3. The built-in Exponential of the ICG360 gives this response to rudder control
Automatic Tail Stabilisation (ATS)
In Heading Lock mode the ICG360 requires NO ATS. Use of ATS in this mode will give unwanted
heading changes. Similarly, no Throttle-to-Tail Rotor mixing should be used in this mode. In Standard
mode you may find
very small
amounts of ATS or Throttle-to-Tail Rotor mixing useful.
Pilot Authority Mixing
This should
not
be used with the ICG360 gyro.
Tail rotor dynamics
To realise the full benefit of the ICG360 it is important to have a basic understanding of the dynamics of
the tail rotor system. It is a common misbelief that the higher the electronic gyro gain is, the better the
system will work. Whilst this is generally true, the electronic gain is only one part of the tail rotor system
and of equal importance is the amount of tail pitch range available, and the tail rotor disk size. The disk
size is also related to the tail rotor speed. Of course there are other influences on the tail system but
these are the most important and can be grouped together as mechanical gain.
If the mechanical gain is not correct, then the gyro will not be able to function to its best ability. For this
reason it is important to select the correct size servo arm that will give maximum tail pitch movement
without stalling the servo. Note: once this has been setup, increasing the rudder channel ATV/TA will not
increase the servo throw as this is limited electronically by the gyro. The rudder ATV/TA is used instead
to adjust the rotation rate.
Tail blade size
The correct length of tail blade can only be selected by flight testing. There are 2 types of test to
ascertain the correct size:
1) With the model in the hover at its normal flight rpm, making sure the gyro is in heading hold mode,
make a rapid vertical climb for 50 to 60 feet: there should be no discernible rotation of the model. If the
tail does not maintain its position this is a good indication that the diameter is too small. Note: if the
model is over pitched and there is a noticeable drop in rotor rpm during the climbout, then this will
invalidate the test as the tail would probably not be able to cope with this situation regardless of the
setup.
