❏
1. Turn on the transmitter and receiver and center the
trims. If necessary, remove the servo arms from the servos
and reposition them so they are centered. Reinstall the
screws that hold on the servo arms.
❏
2. With the transmitter and receiver still on, check all the
control surfaces to see if they are centered. If necessary,
adjust the clevises on the pushrods to center the control
surfaces.
❏
3. Make certain that the control surfaces and the
carburetor respond in the correct direction as shown in the
diagram. If any of the controls respond in the wrong
direction, use the servo reversing in the transmitter to
reverse the servos connected to those controls. Be certain
the control surfaces have remained centered. Adjust if
necessary.
Use a Great Planes AccuThrow (or a ruler) to accurately
measure and set the control throw of each control surface
as indicated in the chart that follows. If your radio does not
have dual rates, we recommend setting the throws at the
low rate setting.
Note: The throws are measured at the widest part of the
elevators, rudder and ailerons.
At this stage the model should be in ready-to-fly condition
with all of the systems in place including the engine, landing
gear, covering and paint, and the radio system.
More than any other factor, the C.G. (balance point) can
have the greatest effect on how a model flies, and may
determine whether or not your first flight will be
successful. If you value this model and wish to enjoy it for
many flights, DO NOT OVERLOOK THIS IMPORTANT
PROCEDURE. A model that is not properly balanced will
be unstable and possibly unflyable.
Balance the Model (C.G.)
IMPORTANT: The Viper 500 ARF has been extensively
flown and tested to arrive at the throws at which it flies
best. Flying your model at these throws will provide you
with the greatest chance for successful first flights. If, after
you have become accustomed to the way the Viper 500
ARF flies, you would like to change the throws to suit your
taste, that is fine. However, too much control throw could
make the model difficult to control, so remember, “more is
not always better.”
These are the recommended control surface throws:
High Rate
Low Rate
ELEVATOR:
1/4" [6mm] up
1/8" [3mm] up
1/4" [6mm] down
1/8" [3mm] down
RUDDER:
1/4" [6mm] right
1/4" [6mm] left
AILERONS:
3/8" [9.5mm] up
1/8" [3mm] up
3/8" [9.5mm] down
1/8" [3mm] down
Set the Control Throws
4-CHANNEL
TRANSMITTER
TRANSMITTER
4-CHANNEL
TRANSMITTER
4-CHANNEL
TRANSMITTER
4-CHANNEL
Check the Control Directions
GET THE MODEL READY TO FLY
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