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Landing flight take off – Great Planes Giant U-Can-Do 3D - GPMA1271 User Manual

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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 take off, 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 tailwheel on
the ground. If necessary, adjust the tailwheel 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 take off 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 tailwheel
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 taildragger 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
take off, most models fly more smoothly at reduced speeds.

Take it easy with the Giant U-CAN-DO 3D ARF 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 tailwheel 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

Take Off

CAUTION (THIS APPLIES TO ALL R/C AIRPLANES): If,
while flying, you notice an alarming or unusual sound such
as a low-pitched “buzz,” this may indicate control surface

flutter

. Flutter occurs when a control surface (such as an

aileron or elevator) or a flying surface (such as a wing or
stab) rapidly vibrates up and down (thus causing the noise).
In extreme cases, if not detected immediately, flutter can
actually cause the control surface to detach or the flying
surface to fail, thus causing loss of control followed by an
impending crash. The best thing to do when flutter is
detected is to slow the model immediately by reducing
power, then land as soon as safely possible. Identify which
surface fluttered (so the problem may be resolved) by
checking all the servo grommets for deterioration or signs of
vibration. Make certain all pushrod linkages are secure and
free of play. If it fluttered once, under similar circumstances it
will probably flutter again unless the problem is fixed. Some
things which can cause flutter are; Excessive hinge gap; Not
mounting control horns solidly; Poor fit of clevis pin in horn;
Side-play of wire pushrods caused by large bends;
Excessive free play in servo gears; Insecure servo mounting;
and one of the most prevalent causes of flutter; Flying an
over-powered model at excessive speeds.

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