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Flying, Fuel mixture adjustments, Takeoff – Great Planes P-51 Mustang Sport Fighter .46 EP ARF - GPMA1208 User Manual

Page 25: Flight, Landing

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25

15. Balance your propeller (and spare propellers).

16. Tighten the propeller nut and spinner.

17. Place your name, address, AMA number and telephone

number on or inside your model.

18. Cycle your receiver battery pack (if necessary) and

make sure it is fully charged.

19. If you wish to photograph your model, do so before

your fi rst fl ight.

20. Range check your radio when you get to the fl ying fi eld.

FLYING

The Sport Fighter Mustang is a great-fl ying model that fl ies

smoothly and predictably. It 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 Sport Fighter Mustang 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 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

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 fi nal 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