Great Planes ElectriCub Kit - GPMA0156 - Manual (Page 43)

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(C.G.) is shown on the fuse plan and is located 2-7/8" back
from the leading edge of the wing. This is the balance point
at which your model should balance for your first flights.
After initial trim flights and when you become more
acquainted with your ElectriCub, you may wish to
experiment by shifting the balance up to 5/16" forward or
backward to change its flying characteristics. Moving the
balance forward may improve the smoothness and stability,
but the model may then require more speed for takeoff and
may become more difficult to slow down for landing. Moving
the balance aft makes the model more agile with a lighter,
snappier “feel.” In any case, please start at the location we
recommend. Do not at any time balance your model
outside the recommended range.
❏ 2. With all parts of the model installed (ready to fly) and
the motor battery installed, lift the model at the balance
point. If the tail drops, the model is “tail heavy” and you must
move the servo tray and possibly the receiver battery
forward to balance the model. If the nose drops, it is “nose
heavy” and you must move the servo tray and possibly the
receiver battery toward the tail to balance the model.
Because excess weight is critical to the flight performance
of electrics, it is best to try balancing the plane by moving
the servos and/or the receiver battery.
If you are unable to obtain good balance by moving the
servos and receiver battery, then it will be necessary to add
weight to the nose or tail to achieve the proper balance point.
❏ 3. After the plane is properly balanced, use four #2 x 3/8"
sheet metal screws to secure the servo tray to the servo
tray rails.
❏ 1. Switch on your transmitter, then the receiver. Center the
elevator and rudder servos. Be sure the trim levers on your
transmitter are centered.
❏ 2. Center the elevator. Then, mark the pushrod where it
crosses the middle servo horn hole. Enlarge the servo horn
hole with a 5/64" diameter drill bit.
❏ 3. Make a 90-degree bend in the pushrod on your mark,
then insert it through the enlarged hole in the servo horn.
Secure it with a nylon Faslink
™ .
❏ 4. Repeat steps 2 and 3 for the rudder.
❏ 5. Check that the throttle servo is properly switching the
micro switch on and off. Caution: Make sure the toggle
switch is off and the motor battery is unplugged.
Important: Before installing the wing struts make sure that
the wing washout is correct.
❏ 1. Reinstall the wing on the fuse. Turn the wing and fuse
upside-down in an airplane cradle or on a thick piece of
foam. It must be supported near the center in such a way
that it does not change the washout angle of the wing tips.
❏ 2. Make six 1/4" wide wing strut straps from the 4" nylon
strip material (not the CA hinge material).
❏ 3. Attach the wing strut straps to the ends of the wing
struts with #2 x 3/8" sheet metal screws.
Note: Refer to the detail drawing on the wing plan which
shows how the straps are mounted to the struts. Cut off the
excess portion of the screws.
❏ 4. Refer to the top view of the fuse plan for the location of
the die-cut 1/16" plywood strut backup plates. Glue the
backup plates on the inside of the fuse bottom.
❏ 5. Drill 1/16" pilot holes in the fuse bottom through the
strut backup plate.
❏ 6. Attach the struts to the fuse with #2 x 3/8" sheet
metal screws.
INSTALL THE WING STRUTS
FINISH THE RADIO INSTALLATION
To reduce the weight of the plane, you may trim the length
of the servo tray rails flush with the edge of the servo tray.