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sometimes cause the surface to break away from the aircraft
and cause a crash. There are many reasons for this, but the
most common are excessive hinge gap or excessive “slop” in
the pushrod connections and control horns. If you ever hear a
low-pitched buzzing sound, reduce throttle and land
immediately.
Frequency Control
- The FCC has allowed the 72MHz band
to be used for R/C aircraft operations. This band is divided up
into many different channels in which you can choose a radio
system. You should be aware that certain areas have
frequencies in which there is pager interference. This is why it
is always a wise move to check with your local hobby shop to
find out any channels that may be troublesome in the area you
wish to fly.
Fuel Overflow Line
(Vent) - The fuel line is either open to
atmospheric pressure or attaches to the muffler pressure
nipple to pressurize the fuel tank for better fuel flow to the
engine. This is the line through which the fuel will overflow
when the tank is full.
Fuel Pick Up-Line
- The fuel line in the fuel tank through
which fuel travels to the carburetor. Typically a flexible tube
with a weight or “Clunk” on the end which allows it to follow the
fuel with changes in aircraft attitude. This is the line through
which the tank is filled.
Fuselage
- The body of an airplane.
Glitch
- Momentary radio problem that never happens unless
you are over trees or a swamp.
Glow Plug
- The heat source for igniting the fuel/air mixture in
the engine. When starting the engine a battery is used to heat
the filament. After the engine is running, the battery can be
removed. The wire filament inside the plug is kept hot by the
“explosions” in the engine’s cylinder. (See next heading and
“Idle Bar” Plug.)
Glow Plug Clip/Battery
- A 1.2-volt battery, which is
connected to the glow plug on a model airplane engine for
starting. The battery is removed once the engine is running
steadily.
Grease-In
- A very smooth, gentle landing without a hint of a
bounce.
Hit
(or to be hit) - Sudden radio interference which causes
your model to fly in an erratic manner. Most often caused by
someone turning on a radio that is on your frequency, but can
be caused by other radio sources miles away.
Horizontal Stabilizer
- The horizontal tail surface at the back
of the fuselage which provides aerodynamic pitch stability to
the airplane.
Idle Bar Plug
- This type of glow plug has a “bar” across the
tip to help prevent raw fuel from being splashed onto the glow
element. Too much raw fuel will cool the plug and prevent it
from igniting the fuel/air mixture. An idle bar is a help in
obtaining a low idle speed.
Lateral Balance
- The left-right or side-to-side balance of an
airplane. An airplane that is laterally balanced will track better
through loops and other maneuvers.
Leading Edge
(LE) - The very front edge of the wing or
stabilizer. This is the edge that hits the air first.
Muffler
- A device attached to the exhaust stack of the engine
to reduce noise and increase back pressure which helps low
speed performance.
Note:
Most R/C Clubs require the use of
mufflers.
Muffler Baffle
- A restrictor plate inside the muffler which
reduces engine noise. This plate can be removed to increase
power, but only if there are no noise restrictions where you fly.
Needle Valve
- Adjustment on a carburetor used to set proper
fuel/air mixture. Some carburetors have separate needle
adjustments for low and high throttle. Typically, turning the
needle clockwise (screwing in) leans the mixture (less fuel),
and vice versa. However, there are a few exceptions—refer to
the engine manufacturer’s instructions.
NiCd
- Nickel Cadmium battery. Rechargeable batteries which
are typically used as power for radio transmitters and
receivers.
Nitro
- Nitromethane, a fuel additive which increases a model
engine’s ability to idle low and improves high speed
performance. Ideal nitro content varies from engine to engine.
Refer to the engine manufacturer’s instructions for best
results. Nitro content in fuel is indicated by the percent of
the fuel.
Ni-Starter
- A self-contained battery and glow plug clip, used
when starting the engine. (See Glow Plug Clip.)
One-Point Landing
(or a figure 9) - Synonymous with “stuffing
it in.” Something we hope you never do.
Pitch Axis
- The airplane axis controlled by the elevator. Pitch
is illustrated by holding the airplane at each wingtip. Raising or
lowering the nose is the pitch movement. This is how the climb
or dive is controlled.
Power Panel
- 12-volt distribution panel that provides correct
voltage for accessories like glow-plug clips, fuel pumps and
electric starters. Usually mounted on a field box and
connected to a 12-volt battery.
Prop Pitch
- Props are designated by these two numbers, for
instance 10 - 6. The first number is the prop’s length, 10". The
second number is the pitch or angle of the blades. The 6
represents the distance the propeller will move forward in one
revolution, in this case 6".
