Top Flite TOPA0955 - Manual (Page 32)

32
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 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 .
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 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, and 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 .
FLIGHT
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 P-47 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 .
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 . Deploy
the flaps . A small amount of ballooning will occur but
the plane should begin to settle as you lose speed .
We found that mixing in 2 degrees of down elevator
minimized this tendency . You may wish to experiment
with a flap to elevator mix) . When deploying the flaps
do not allow the plane to pitch up and stall . Make
elevator corrections as needed to maintain a steady
descent . (
Note: Flaps are not required for landing but
they will substantially reduce the landing speed. We
recommend the use of flaps for the P-47.) 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
decrease the engine and touch down level on the
main wheels . The tail will settle on the runway as you
begin to lose speed . 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 .
From our experience, this plane lands best if you do
a two point landing on the main wheels rather than
trying to flare to a three point landing .
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