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Landing flight takeoff – Great Planes Spitfire 25 GP/EP ARF - GPMA1478 User Manual

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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 skid on the
ground. 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, 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
takeoff, most models fly more smoothly at reduced speeds.

Take it easy with the Combat Spitfire 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 flight time, 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.

Have a ball! But always stay in control and fly

in a safe manner.

GOOD LUCK AND GREAT FLYING!

Landing

Flight

Takeoff

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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