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Balance the model (c.g.) – Great Planes Escapade .61 GP/EP ARF - GPMA1201 User Manual

Page 24

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5. Measure and set the

low rate

elevator throws and the

high and low rate throws for the rest of the control surfaces
the same way.

These are the recommended control surface throws:

ELEV

A

T

OR

R

UDDER

AILER

ONS

LOW RATE

7/8"

[22mm]

14°

Up & Down

3/8"

[10 mm]

12°

Up & Down

1- 3/4"

[44mm]

19°

Right & Left

HIGH RATE

1-1/2"

[38mm]

25°

Up & Down

3/4"

[19mm]

25°

Up & Down

2-1/2"

[64 mm]

28°

Right & Left

If your radio does not have dual rates, we recommend setting
the throws at the low rate settings until you become familiar
with the airplane. You might later consider to set them to the
high rate settings.

NOTE

: The throws are measured at the

widest part

of the

elevators, rudder and ailerons.

Balance the Model (C.G.)

More than any other factor, the C.G. (center of gravity/
balance point) can have the greatest effect on how a model
fl ies and could determine whether or not your fi rst fl ight will
be successful. If you value your model and wish to enjoy it
for many fl ights,

DO NOT OVERLOOK THIS IMPORTANT

PROCEDURE.

A model that is not properly balanced may

be unstable and possibly unfl yable.

At this stage the model should be in ready-to-fl y condition

with

all

of the components in place including the complete

radio system, engine, muffl er, propeller, spinner and pilot. If
you’ve built the electric version, install the motor battery. If
you’ve built the glow version the fuel tank should be empty.

1. If using a Great Planes C.G. Machine

, set the rulers

to 4" [102mm]. If not using a C.G. Machine, use a fi ne-point
felt tip pen to mark lines on the top of wing on both sides of
the fuselage 4" [102mm] back from the leading edge. Apply
narrow (1/16" [2mm]) strips of tape over the lines so you will
be able to feel them when lifting the model with your fi ngers.

This is where your model should balance for the fi rst
fl ights. Later, you may experiment by shifting the C.G. 3/16"
[4.8mm] forward or 1" [25mm] back to change the fl ying
characteristics. Moving the C.G. forward will improve the
smoothness and stability, but the model will then be less
aerobatic (which may be fi ne for less-experienced pilots).
Moving the C.G. aft makes the model more maneuverable
and aerobatic for experienced pilots. In any case,

start at

the recommended balance point

and do not at any time

balance the model outside the specifi ed range.

4" [102 mm]

Great Planes

C.G. Machine

2. With the wing attached to the fuselage, all parts of the

model installed (ready to fl y) and an empty fuel tank, place
the model upside-down on a Great Planes CG Machine, or
lift it upside-down at the balance point you marked.

3. If the tail drops, the model is “tail heavy.” If possible, move

the battery pack and/or receiver forward to get the model to
balance. If the nose drops, the model is “nose heavy.” If possible,
move the battery pack and/or receiver aft. If the receiver and/
or battery cannot be moved, or if additional weight is still
required, nose weight may be easily added by using “spinner
weight” (GPMQ4645 for the 1 oz. [28g] weight, or GPMQ4646
for the 2 oz. [57g] weight). If spinner weight is not practical or
is not enough, or if tail weight is required, use Great Planes

“stick-on” lead (GPMQ4485). To fi nd out how much weight is

required, place incrementally increasing amounts of weight on
the bottom of the fuselage over the location where it would be
mounted inside until the model balances. A good place to add
stick-on nose weight is to the fi rewall. Do not attach weight to
the cowl—this will cause the mounting screws to open up the
holes in the cowl. Once you have determined the amount of
weight required, it can be permanently attached. If required,
tail weight may be added by cutting open the bottom of the
fuse and gluing it permanently inside.

Note:

If mounting weight where it may be exposed to fuel

or exhaust, do not rely upon the adhesive on the back to
permanently hold it in place. Over time, fuel and exhaust
residue may soften the adhesive and cause the weight to fall
off. Instead, permanently attach the weight with glue or screws.

4.

IMPORTANT:

If you found it necessary to add any weight,

recheck the C.G. after the weight has been installed.