NOTE: This section is VERY important and must NOT be
omitted! A model that is not properly balanced will be
unstable and possibly unflyable.
At this stage your 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.
❏
1. Accurately mark the C.G. on the top of the wing on
both sides of the fuselage.
The C.G. is located 4-3/16"
[106mm] back from the leading edge of the wing.
This is
where your model should balance for your first flights. Later,
you may wish to experiment by shifting the C.G. up to 1/4"
[6.4mm] forward or back to change the flying characteristics.
Moving the C.G. forward may improve the smoothness and
arrow-like tracking, but it may then require more speed for
takeoff and make it more difficult to slow down for landing.
Moving the C.G. aft makes the model more agile with a
lighter and snappier feel. In any case, start at the location
we recommend and do not at any time balance your model
outside the recommended range.
❏
2. With the wing attached to the fuselage, all parts of the
model installed (ready to fly) 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” and weight
must be added to the nose to balance. If the nose drops, the
model is “nose heavy” and weight must be added to the tail
to balance. Nose weight may be easily added by using a
“spinner weight” (GPMQ4645 for the 1 oz. weight, or
GPMQ4646 for the 2 oz. weight). If spinner weight is not
enough use Great Planes (GPMQ4485) “stick-on” lead. A
good place to add stick-on nose weight is to the firewall
(don't attach weight to the cowl—it is not intended to support
weight). Begin by placing incrementally increasing amounts
of weight on the bottom of the fuse over the firewall until the
model balances. 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:
Do not rely upon the adhesive on the back of the lead
weight to permanently hold it in place. Over time, fuel and
exhaust residue may soften the adhesive and cause the
weight to fall off. Use #2 sheet metal screws, RTV silicone
or epoxy to permanently hold the weight in place.
❏
4.
IMPORTANT
: If you found it necessary to add any
weight, recheck the C.G. after the weight has been installed.
❏
1. With the wing level, have an assistant help you lift the
model by the engine propeller shaft and the bottom of the
fuse under the TE of the fin. Do this several times.
❏
2. If one wing always drops when you lift the model, it means
that side is heavy. Balance the airplane by adding weight to the
other wing tip.
An airplane that has been laterally balanced
will track better in loops and other maneuvers.
Balance the Model Laterally
4-3/16" [106mm]
4-3/16" [106mm]
From LE
Balance the Model
We recommend the following control surface throws:
High Rate
Low Rate
ELEVATOR:
1" [25mm] up
3/4" [19mm] up
1" [25mm] down
3/4" [19mm] down
RUDDER:
1-9/16" [40mm] right 1-3/8" [35mm] right
1-9/16" [40mm] left
1-3/8" [35mm] left
AILERONS:
3/4" [19mm] up
1/2" [13mm] up
3/4" [19mm] down
1/2" [13mm] down
IMPORTANT
: The balance point and control surface
throws listed in this manual are the ones at which the Ryan
flies best. Set up your aircraft to those specifications. If,
after a few flights, you would like to adjust the throws or
C.G. to suit your tastes, that is fine. Too much control
surface throw can make your model difficult to control or
force it into a stall, so remember “more is not always better.”
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