24
Set the Control Throws
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.
These are the recommended
high
and
low
rate control
surface throws. If setting up your model with
3D
throws for extreme aerobatics, refer to the 3D chart:
LOW RATE
ELEVATOR:
3/8" [9.5mm], 6° up
3/8" [9.5mm], 6° down
RUDDER:
2" [51mm], 16° left
2" [51mm], 16° right
AILERONS:
3/8" [9.5mm], 6° up
3/8" [9.5mm], 6° down
HIGH RATE
ELEVATOR:
3/4" [19mm], 11° up
3/4" [19mm], 11° down
RUDDER:
2-3/4" [70mm], 22° left
2-3/4" [70mm], 22° right
AILERONS:
3/4" [19mm], 14° up
3/4" [19mm], 14° down
3D CONTROL THROWS
Unless you are an extremely experienced 3D pilot, if
setting up your Extra 300S .46 with 3D throws, you
should be able to switch to high or low rate throws during
fl ight in case you fi nd the 3D throws too extreme.
ELEVATOR:
3" [76mm], 51° up
3" [76mm], 51° down
RUDDER:
5" [127mm], 44° left
5" [127mm], 44° right
AILERONS:
1-3/8" [34.5mm], 26° up
1-3/8" [34.5mm], 26° down
IMPORTANT:
The Great Planes Extra 300SP .46 ARF has
been
extensively
fl own and tested to arrive at the throws
at which it fl ies best. Flying your model at these throws
will provide you with the greatest chance for successful
fi rst fl ights. If, after you have become accustomed to the
way the Extra 300SP fl ies, you would like to change the
throws to suit your taste, that is fi ne. However, too much
control throw could make the model diffi cult to control, so
remember, “more is not always better.”
Balance the Model (C.G.)
More than any other factor, the
C.G.
(balance point)
can have the
greatest
effect on how a model fl ies, and
may determine whether or not your fi rst fl ight will be
successful. If you value this model and wish to enjoy it for
many fl ights,
DO NOT OVERLOOK THIS IMPORTANT
PROCEDURE.
A model that is not properly balanced will
be unstable and possibly unfl yable.
At this stage the model should be in ready-to-fl y condition
with all of the systems in place including the engine, propeller
and spinner, landing gear, and the complete radio system.
Electric-powered models should balanced with the fl ight
batteries installed, but not connected.
3-3/4" [95mm]
❏
1. If you will be using a Great Planes C.G. Machine, set
the rulers to 3-3/4" [95mm]. If not using a Great Planes C.G.
Machine, slide the wings together with the aluminum joiner.
Use a straightedge and a fi ne-point felt-tip pen to mark the
balance point on the top of both wings 3-3/4" [95mm] back
from the leading edges where they meet the fuselage. Place
1/16" to 1/8" [1.5 to 3mm] strips of tape over the lines you
marked so you will be able to feel the balance point with your
fi ngers when lifting the model to balance.
This is where your model should balance for the fi rst
fl ights. Later, you may wish to experiment by shifting
the C.G. up to 1/2" [12mm] forward or 3/4" [19mm] back
to change the fl ying characteristics. Moving the C.G.
forward may improve the smoothness and stability, but
the model may then require more speed for takeoff and
make it more diffi cult to slow for landing. Moving the C.G.
aft makes the model more maneuverable, but could also
cause it to become too diffi cult to control. In any case,
start at the recommended balance point
and do not at
any time balance the model outside the specifi ed range.
❏
2. Join the wings to the fuselage. With all parts of the
model installed (ready to fl y) and an empty fuel tank (or with
the batteries installed for electric models), place the model
upside-down on a Great Planes CG Machine; or, turn it over
and lift it upside down placing your fi ngers on the thin strips
of tape at the balance point you marked.