Range Test Your Radio
Step 1.
Before each flying session, be sure to range check your
radio. This is accomplished by turning on your transmitter with
the antenna collapsed. Turn on the receiver in your airplane.
With your airplane on the ground and the engine running, you
should be able to walk 30 paces (approximately 100 feet) away
from your airplane and still have complete control of all
functions. If not, don’t attempt to fly! Have your radio equipment
checked out by the manufacturer.
Step 2.
Double-check that all controls (aileron, elevator,
rudder, and throttle) move in the correct direction.
Step 3.
Be sure that your batteries are fully charged, per the
instructions included with your radio.
Preflight at the Field
32
A 7-channel or greater computer radio is highly recommended.
This allows the following features:
• Mixing the right aileron to the left aileron (flaperon mix)
• Electronically adjustable aileron differential
• Mixing the right elevator to the left elevator
(dual elevator mixing)
• Independent travel and trim adjustments of
each elevator half
• Mixing the right rudder servo to the left rudder servo
• Rudder to elevator mixing to correct rudder to
elevator coupling
• Rudder to aileron mixing to correct rudder to
aileron coupling
When using a 7-channel or greater computer radio, each servo is
plugged into its own separate channel. Consult your radio
manual for specific details on hookup and programming.
If using a 6-channel radio with flaperon mix, the aileron servos
are each plugged into their own channels. The right aileron plugs
into the aileron socket in the receiver, while the left aileron plugs
into channel 6. With flaperon activated in the programming, this
allows for independent travel adjustment of each aileron in each
direction and electronic aileron differential. Consult your manual
for more programming details.
With a 6-channel computer radio, it will be necessary to
Y-harness the 2 rudder and elevator servos; a reversed elevator
servo is needed to achieve the correct control direction. A servo
reverser can be used here. Special attention must be taken with
the rudder servos so that they don’t fight each other throughout
the rudder travel. This is caused by nonsymmetrical pushrod
geometry from right to left. It may be necessary to rotate the arm
on the servo one or two splines (most of the time toward the
rear) and readjust the linkage length in order to prevent binding.
Using a non-computer radio will require that the aileron,
elevator, and rudder be Y-harnessed. Be sure to use a reversed
servo (or a reverser) for one of the elevator servos. Special
attention must be taken with the rudder servos so that they don’t
fight each other throughout the rudder travel. This is caused by
non-symmetrical pushrod geometry from right to left. It may be
necessary to rotate the arm on the servo one or two splines
(most of the time toward the rear) and readjust the linkage length
in order to prevent binding. If you’ve ever thought about
purchasing a computer radio, now is a good time to do it!
Section 14: Radio Setup
Recommended Control Throws
Standard
3D
Aileron
1
1
/
2
" up 1
1
/
8
" down (18° up 17° down)
2
1
/
2
" up 2
1
/
4
" down (37° up 35° down)
Elevator
1
3
/
8
" up 1
1
/
2
" down (16° up 15° down)
4" up 4
1
/
4
" down (42° up 44° down)
Rudder
4
1
/
2
" right and left (26°)
8" right and left (44°)
Section 15: Control Throws
