19
E-flite Piper L-4 Grasshopper ARF Assembly Manual
Aileron Low Rate
Exponential
Up
3/8-inch
(10mm)
0%
Down
5/16-inch (8mm)
0%
Aileron High Rate
Up
1/2-inch
(12mm)
10%
Down
3/8-inch
(10mm)
10%
Elevator Low Rate
Up
9/32-inch (7mm)
0%
Down
9/32-inch (7mm)
0%
Elevator High Rate
Up
3/8-inch
(10mm)
10%
Down
3/8-inch
(10mm)
10%
Rudder Low Rate
Left
1/2-inch
(12mm)
5%
Right
1/2-inch
(12mm)
5%
Rudder High Rate
Left
13/16-inch (20mm)
15%
Right
13/16-inch (20mm)
15%
Measurements are taken at the inner or
widest point on the control surface.
These are general guidelines measured from our own
flight tests. You can experiment with higher rates to
match your preferred style of flying.
Travel Adjust, Sub-Trim and Dual Rates are
not listed and should be adjusted according
to each individual model and preference.
Center of Gravity
An important part of preparing the aircraft for flight is
properly balancing the model.
Caution: Do not inadvertently skip this step!
The recommended Center of Gravity (CG) location for
your model is 1
9
/
16
- to 1
15
/
16
-inches (40–50mm) back
from the leading edge of the wing at the root. Make
sure to measure from the farthest point forward for
accuracy. Mark the location for the Center of Gravity
on the bottom of the wing next to the fuselage as
shown.
With the model upright, adjust components as
necessary so the model hangs level or slightly nose
down. This is the correct balance point for your model.
You might find that you need to shift the battery slightly
to either the front or back of the fuselage to achieve
the correct balance.
It may be necessary to add a small amount of weight
(0.25–0.6 ounces) inside the cowling to correctly
balance your model. Using the optional Thunder Power
730mAh battery will not require the addition of any
weight to your model.
After the first flights, the CG position can be adjusted
for your personal preference.
Range Test Your Radio
Before each flying session, and especially with a new
model, it is important to perform a range check. It
is helpful to have another person available to assist
during the range check. If you are using a Spektrum
transmitter, please refer to your transmitter’s manual for
detailed instructions on the range check process.
1. With the model resting on the ground, stand 30
paces (approximately 90 feet) away from the model.
2. Face the model with the transmitter in your
normal flying position. Be sure the throttle is in the
full down position and plug the flight battery into
the speed control.
3. As you move the controls, watch to be sure the
airplane’s motor and controls operate smoothly.
You should have total control of the model at 30
paces (90 feet).
4. If control issues exist, call the Horizon Support
Team at 1 877 504 0233 or go to
horizonhobby.
com
to find a local Spektrum distributor in your
country for service if you are using a Spektrum
radio system.
