Flying; Takeoff; Flight; Landing - GREAT PLANES SU-31 Instruction Manual

The Sukhoi SU-31 EP ARF is a great-flying model that flies
smoothly and predictably. The Sukhoi SU-31 EP ARF does not,
however, possess the self-recovery characteristics of a primary
R/C trainer and should be flown only by experienced R/C pilots.
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.
If you have access to a smooth, paved runway, we suggest
using it to takeoff, especially for the first few flights. Position
the Sukhoi SU-31 EP ARF onto the runway pointed into the
wind. Slowly advance the throttle stick to half throttle, leaving
the elevator in the neutral position. As the tail rises off the
ground, slowly increase throttle and apply a bit of up elevator
to lift the model into the air. As you become accustomed to the
takeoff characteristics of the Sukhoi SU-31 EP ARF, they can
be performed quickly, only requiring five to ten feet of runway
until the model is airborne.
If you do not have access to a smooth runway, the Sukhoi
SU-31 EP ARF can be hand launched. For the first flight, it
is a good idea to have someone launch the airplane for you.
This allows you to keep your hands on the radio sticks and
correct any trim problems that are present.
Have the person launching the Sukhoi SU-31 EP ARF hold
the plane by the fuselage just below the canopy. Throttle up
to full power and have your helper give the plane a gentle,
underhanded toss at about a 30° angle upward into the wind.
The high thrust-to-weight ratio will allow the plane to accelerate
to flying speed almost instantly. Climb to a comfortable altitude
and throttle back to a lower power setting.

FLYINg

Takeoff

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 Sukhoi SU-31 EP 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 battery charge, 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.
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.
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Flight

Landing