Great Planes U-Can-Do 3D 60 ARF - GPMA1270 - Manual (Page 25)

Don't get spoiled by how incredibly well the U-Can-Do 3D
hangs and torque rolls! Most models take an enormous
amount of work to keep the model stationary in a hanger, but
the unique design of U-Can-Do 3D helps lock it solid in
position and torque roll and hang with relative ease.
Fuel Mixture Adjustments
A fully cowled engine may run at a higher temperature than
an un-cowled engine. For this reason, the fuel mixture
should be richened so the engine runs at about 200 rpm
below peak speed. By running the engine slightly rich, you
will help prevent dead-stick landings caused by overheating.
Before you get ready to takeoff, see how the model handles
on the ground by doing a few practice runs at low speeds
on the runway. Hold “up” elevator to keep the tail wheel on
the ground. If necessary, adjust the tail wheel so the model
will roll straight down the runway. If you need to calm your
nerves before the maiden flight, shut the engine down and
bring the model back into the pits. Top off the fuel, then
check all fasteners and control linkages for peace of mind.
Remember to takeoff into the wind. When you're ready, point
the model straight down the runway, hold a bit of up elevator
to keep the tail on the ground to maintain tail wheel steering,
then gradually advance the throttle. As the model gains
speed decrease up elevator, allowing the tail to come off the
ground. One of the most important things to remember with
a tail dragger is to always be ready to apply right rudder to
counteract engine torque. Gain as much speed as your
runway and flying site will practically allow before gently
applying up elevator, lifting the model into the air. At this
moment it is likely that you will need to apply more right
rudder to counteract engine torque. Be smooth on the
elevator stick, allowing the model to establish a gentle climb
to a safe altitude before turning into the traffic pattern.
For reassurance and to keep an eye on other traffic, it is a
good idea to have an assistant on the flight line with you. Tell
him to remind you to throttle back once the plane gets to a
comfortable altitude. While full throttle is usually desirable for
takeoff, most models fly more smoothly at reduced speeds.
Take it easy with the U-CAN-DO-3D for the first few flights,
gradually getting acquainted with it as you gain confidence.
Adjust the trims to maintain straight and level flight. After flying
around for a while and while still at a safe altitude with plenty of
fuel, practice slow flight and execute practice landing
approaches by reducing the throttle to see how the model
handles at slower speeds. Add power to see how she climbs as
well. Continue to fly around, executing various maneuvers and
making mental notes (or having your assistant write them down)
of what trim or C.G. changes may be required to fine tune the
model so it flies the way you like. Mind your fuel level, but use
this first flight to become familiar with your model before landing.
To initiate a landing approach, lower the throttle while on the
downwind leg. Allow the nose of the model to pitch downward
to gradually bleed off altitude. Continue to lose altitude, but
maintain airspeed by keeping the nose down as you turn onto
the crosswind leg. Make your final turn toward the runway (into
the wind) keeping the nose down to maintain airspeed and
control. Level the attitude when the model reaches the runway
threshold, modulating the throttle as necessary to maintain
your glide path and airspeed. If you are going to overshoot,
smoothly advance the throttle (always ready on the right
rudder to counteract torque) and climb out to make another
attempt. When you're ready to make your landing flare and the
model is a foot or so off the deck, smoothly increase up
elevator until it gently touches down. Once the model is on the
runway and has lost flying speed, hold up elevator to place the
tail on the ground, regaining tail wheel control.
One final note about flying your model. Have a goal or flight plan
in mind for every flight. This can be learning a new
maneuver(s), improving a maneuver(s) you already know, or
learning how the model behaves in certain conditions (such as
on high or low rates). This is not necessarily to improve your
skills (
though it is never a bad idea!), but more importantly so
you do not surprise yourself by impulsively attempting a
maneuver and suddenly finding that you've run out of time,
altitude or airspeed. Every maneuver should be deliberate, not
impulsive. For example, if you're going to do a loop, check your
altitude, mind the wind direction (anticipating rudder corrections
that will be required to maintain heading), remember to throttle
back at the top and make certain you are on the desired rates
(high/low rates). A flight plan greatly reduces the chances of
crashing your model just because of poor planning and
impulsive moves. Remember to think. Have a ball! But
always stay in control and fly in a safe manner.
GOOD LUCK AND GREAT FLYING!
Landing
Flight
Takeoff
CAUTION (THIS APPLIES TO ALL R/C AIRPLANES): If,
while flying, you notice any unusual sounds, such as a low-
pitched “buzz,” this may indicate control surface
flutter.
Because flutter can quickly destroy components of your
airplane, any time you detect flutter you must immediately
cut the throttle and land the airplane! Check all servo
grommets for deterioration (this may indicate which surface
fluttered) and make sure all pushrod linkages are secure and
free of play. If the control surface fluttered once, it probably
will flutter again under similar circumstances unless you can
eliminate the free-play or flexing in the linkages. Here are
some things which can cause flutter: Excessive hinge gap;
Not mounting control horns solidly; Poor fit of clevis pin in
horn; Side-play of pushrod in guide tube caused by tight
bends; Poor fit of Z-bend in servo arm; Insufficient glue used
when gluing in the elevator joiner wire; Excessive
play or
backlash in servo gears; and Insecure servo mounting.
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