User Manual

30
3. With the wings attached to the fuselage, all parts of the
model installed (ready to fl y) and an empty fuel tank, place
the model on your Great Planes CG Machine, or lift it at the
balance point you marked.
4. If the tail drops, the model is “tail heavy” and the battery
pack and/or receiver must be shifted forward or weight must
be added to the nose to balance. If the nose drops, the model
is “nose heavy” and the battery pack and/or receiver must be
shifted aft or weight must be added to the tail to balance. If
possible, relocate the battery pack and receiver to minimize
or eliminate any additional ballast required. If additional
weight is required, nose weight may be easily added by using
a “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, use Great Planes (GPMQ4485)
“stick-on” lead. A good place to add stick-on nose weight is to
the fi rewall (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 fi rewall
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.
5. IMPORTANT: If you found it necessary to add any
weight, recheck the C.G. after the weight has been installed.
Balance the Model Laterally
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 fi n. 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.
PREFLIGHT
Identify Your Model
No matter if you fl y at an AMA sanctioned R/C club site or
if you fl y somewhere on your own, you should always have
your name, address, telephone number and AMA number
on or inside your model. It is required at all AMA R/C club
ying sites and AMA sanctioned fl ying events. Fill out the
identifi cation tag on page 35 (or on the decal sheet) and
place it on or inside your model.
Charge the Batteries
Follow the battery charging instructions that came with your
radio control system to charge the batteries. You should
always charge your transmitter and receiver batteries
the night before you go fl ying, and at other times as
recommended by the radio manufacturer.
CAUTION: Unless the instructions that came with your
radio system state differently, the initial charge on new
transmitter and receiver batteries should be done for 15
hours using the slow-charger that came with the radio
system. This will “condition” the batteries so that the next
charge may be done using the fast-charger of your choice.
If the initial charge is done with a fast-charger the batteries
may not reach their full capacity and you may be fl ying
with batteries that are only partially charged.
Balance Propellers
Carefully balance your propeller and spare propellers before
you fl y. An unbalanced prop can be the single most signifi cant
cause of vibration that can damage your model. Not only
will engine mounting screws and bolts loosen, possibly with
disastrous effect, but vibration may also damage your radio
receiver and battery. Vibration can also cause your fuel to
foam, which will, in turn, cause your engine to run hot or quit.
We use a Top Flite Precision Magnetic Prop Balancer
(TOPQ5700) in the workshop and keep a Great Planes
Fingertip Prop Balancer (GPMQ5000) in our fl ight box.