Top Flite TOPA0706 - Manual (Page 33)

33
Current AMA maximums for engine displacement are
6.0 cu. in. for two-stroke and 9.6 cu. in. for four-stroke
engine. These maximums apply only to AMA Sanctions
concerning competition events (such as 511, 512, 515
and 520) and, as such, the maximums apply. All IMAA
(non competition) events should be sanctioned as Class
“C” events, in which these engine size maximums do
not apply.
Generally, it is recommended that no attempt should
be made to fl y a radio controlled model aircraft with
a gasoline engine in which the model aircraft weight
would exceed twelve (12) pounds (underpowered) per
cubic inch of engine displacement, or be less than fi ve
(5) pounds (overpowered) per cubic inch of engine
displacement. Example: Using a 3 cu. in. engine, a
model would likely be underpowered at an aircraft
weight greater than 36 pounds. With the same engine,
an aircraft weighing less than 15 pounds would likely
be overpowered.
Servo arms and wheels should be rated heavy duty.
Glass-fi lled servo arms and control horns are highly
recommended.
Propeller tips should be painted or colored in a visible
and contrasting manner so as to increase the visibility
of the propeller tip arc.
FLYING
The Giant FW 190A-3 ARF is a great-fl ying model that
fl ies smoothly and predictably. The Giant FW 190A-3
ARF does not, however, possess the self-recovery
characteristics of a primary R/C trainer and should be
fl own only by experienced R/C pilots.
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.
CAUTION (THIS APPLIES TO ALL R/C AIRPLANES):
If, while fl ying, you notice an alarming or unusual
sound such as a low-pitched “buzz,” this may indicate
control surface fl utter. Flutter occurs when a control
surface (such as an aileron or elevator) or a fl ying
surface (such as a wing or stab) rapidly vibrates up
and down (thus causing the noise). In extreme cases,
if not detected immediately, fl utter can actually cause
the control surface to detach or the fl ying surface
to fail, thus causing loss of control followed by an
impending crash. The best thing to do when fl utter
is detected is to slow the model immediately by
reducing power, then land as soon as safely possible.
Identify which surface fl uttered (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 fl uttered once, under similar circumstances it will
probably fl utter again unless the problem is fi xed.
Some things which can cause fl utter are; Excessive
hinge gap; Not mounting control horns solidly; Poor
fi t 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 fl utter; Flying an over-powered
model at excessive speeds.
TAKEOFF
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 fl ight,
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 fl ying 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 traffi c pattern.
FLIGHT
For reassurance and to keep an eye on other traffi c, it
is a good idea to have an assistant on the fl ight 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 fl y more
smoothly at reduced speeds.
Take it easy with the Giant FW 190A-3 ARF for the fi rst
few fl ights, gradually getting acquainted with it as you
gain confi dence. Adjust the trims to maintain straight and
level fl ight. After fl ying around for a while, and while still
at a safe altitude with plenty of fuel, practice slow fl ight
and execute practice landing approaches by reducing
the throttle and lowering the fl aps to see how the model
handles at slower speeds. Add power to see how she
climbs as well. Continue to fl y 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 fi ne tune the model so it fl ies the way
you like. Mind your fuel level, but use this fi rst fl ight to
become familiar with your model before landing.
LANDING
One of the keys to landing a giant-scale model is to
maintain suffi cient airspeed throughout the landing
approach. An unusually high airspeed is not necessary,
but those unfamiliar with landing giant-scale models are
sometimes deceived by the model’s larger size. Larger
models often appear to be closer than they actually are.
Additionally, most giant-scale models slow down rapidly,
thus causing the uninitiated to land short. To avoid this
initial illusion, make your landing pattern closer than you
normally might for a .40-size sport model. Also, don’t
pull the throttle all the way back and leave it there the