Great Planes Learjet 40 Kit - GPMA0439 - Manual (Page 39)

Radio Control
1 I will have completed a successful radio equipment ground
check before the first flight of a new or repaired model
2. I will not fly my model aircraft in the presence of
spectators until I become a qualified flier, unless assisted
by an experienced helper
3. I will perform my initial turn after takeoff away from the pit
or spectator areas and I will not thereafter fly over pit or
spectator areas, unless beyond my control.
4 I will operate my model using only radio control
frequencies currently allowed by the Federal
Communications Commission.
The best place to fly your R/C model is an AMA
(Academy of Model Aeronautics) chartered club field Ask
your hobby shop dealer if there is such a club in your area
and join Club fields are set up for R/C flying which makes
your outing safer and more enjoyable The AMA can also
tell you the name of a club in your area We recommend
that you join AMA and a local club so you can have a safe
place to fly and also have insurance to cover you in case of
a flying accident (The AMA address is listed in the front of
this instruction book)
If a club and its flying site are not available, you need to
find a large area with at least 300' of smooth surface for a
runway (because of its small wheels the Learjet is not suited
for rough grass runways) The flying site should be at least 6
miles away from any other R/C radio operation like R/C
boats and R/C cars and away from houses, buildings and
streets A schoolyard may look inviting but it is too close to
people, power lines and possible radio interference.
The Learjet is a great looking semi-scale airplane and
a great flying sport model Like its full-size counterpart, the
Great Planes Learjet is capable of graceful aerobatics It
does not have the self-recovery characteristics of a primary
trainer Therefore, you must either have mastered the
basics of R/C flying or obtained the assistance of a
competent R/C pilot to help you with your first flights.
Do a low speed taxi test before your first takeoff If the
plane does not track straight, adjust the steering linkage to
correct the problem Don't adjust the ground steering
with the rudder trim! Although the Learjet has good low
speed flight characteristics, you should not lift the model
into the air until it has built up sufficient air speed, as this
will give you a safety margin in case of a "flame-out" As the
model rolls down the runway, continue to build up speed
and gently apply up elevator Climb out gradually and let it
gain some airspeed before hunting for the clouds For
safety's sake, always remember to make your first turn
away from the pit area If you are using retracts, it's wise to
leave them extended for your first few laps around the field
on a maiden voyage in case of engine failure Once your
confidence in the model is satisfied, the gear may be
retracted when the model is safely airborne
We recommend that you take it easy with your Learjet
for the first several flights and gradually "get acquainted" with
its flying characteristics while your engine gets fully broken-
in Work on trimming the airplane for straight and level flight
with the transmitter trims at neutral, adjusting the clevises or
pushrod cables after each flight Also, take note of the
responsiveness of the elevator, ailerons and rudder, and
adjust their throws to your preference Add and practice one
maneuver at a time, learning how it behaves in each one
The Learjet is a surprisingly lively model — especially with a
"hot" 45 or 46 engine As with any model, high speed dives
and abrupt movements that can lead to flutter and structural
failure should be avoided
CAUTION (THIS APPLIES TO ALL R/C AIRPLANES) If,
while flying, you notice any unusual sounds, such as a
low-pitched "buzz," this may be an indication of control
surface "flutter" Because flutter can quickly destroy
components of your airplane, any time you detect flutter
you must immediately cut the throttle and land the
airplane' Check all servo grommets for deterioration (this
will indicate which surface fluttered), and make sure all
pushrod linkages are slop-free If it fluttered once, it will
probably flutter again under similar circumstances unless
you can eliminate the slop or flexing in the linkages
Here are some things which can result in flutter
Excessive hinge gap Not mounting control horns solidly,
Sloppy fit of clevis pin in horn, Elasticity present in
flexible plastic pushrods, Side-play of pushrod in guide
tube caused by tight bends, Sloppy fit of Z-bend in servo
arm, Insufficient glue used when gluing in the aileron
torque rod, Excessive flexing of aileron, caused by using
too soft balsa aileron, Excessive "play" or "backlash" in
servo gears, and Insecure servo mounting
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