Instruction manual

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".
Receiver (Rx) - The radio unit in the airplane which receives
the transmitter signal and relays the control to the servos.
This is somewhat similar to the radio you may have in your
family automobile, except the radio in the airplane
perceives commands from the transmitter, while the radio
in your car perceives music from the radio station.
Roll Axis - The airplane axis controlled by the ailerons. Roll
is illustrated by holding the airplane by the nose and tail.
Dropping either wing tip is the roll movement. This is used
to bank or turn the airplane. Many aircraft are not equipped
with ailerons and the Roll and Yaw motions are controlled
by the rudder. This is one reason why most trainer aircraft
have a larger amount of dihedral.
Rudder - Hinged control surface located at the trailing
edge of the vertical stabilizer, which provides control of the
airplane about the Yaw axis and causes the airplane to Yaw
left or right. Left rudder movement causes the airplane to
Yaw left, and right rudder movement causes it to Yaw right.
Servo - The electro-mechanical device which moves the
control surfaces or throttle of the airplane according to
commands from the receiver. The radio device which does
the physical work inside the airplane.
Servo Output Arm - The removable arm or wheel which bolts
to the output shaft of a servo and connects to the pushrod.
Shot Down - A “hit” that results in a crash landing.
Sometimes caused by radios miles away.
Slop - Unwanted, excessive free movement in a control
system. Often caused by a hole in a servo arm or control
horn that is too big for the pushrod wire or clevis pin. This
condition allows the control surface to move without
transmitter stick movement. (See Flutter.)
Solo - Your first totally unassisted flight that results in a
controlled landing.
Spinner - The nose cone, which covers the propeller hub.
Sport Airplane - A model which possesses some
attributes of many of the specialty airplanes and are best
for general flying as they are the most versatile and durable.
Stall - What happens when the angle of attack is too great
to generate lift regardless of airspeed. (Every airfoil has an
angle of attack at which it generates maximum lift — the
airfoil will stall beyond this angle).
Tachometer - An optical sensor designed specifically to
count light impulses through a turning propeller and read
out the engine RPM.
Tip Stall - The outboard end of one wing (the tip) stops
developing lift, causing the plane to roll suddenly in the
direction of the stalled wing. This situation is not fun when
you are only a few feet off the runway trying to land.
Trainer Airplane - A model designed to be inherently
stable and fly at low speeds, to give first-time modelers
time to think and react as they learn to fly.
Trailing Edge (TE) - The rearmost edge of the wing or stabilizer.
Transmitter (Tx) - The hand-held radio controller. This is
the unit that sends out the commands that you input.
Touch-And-Go - Landing and taking off without a pause.
Often confused with a good bounce.
Vertical Fin - The non-moving surface that is perpendicular
to the horizontal stabilizer and provides yaw stability. This
is the surface to which the rudder attaches.
Washout - An intentional twist in the wing, causing the
wing tips to have a lower angle of attack than the wing root.
In other words, the trailing edge is higher than the leading
edge at the wing tips. Washout helps prevent tip stalls.
Wheel Collar - A small, round retaining device used to
keep wheels from sliding off an axle.
Wing - The main lifting surface of an airplane.
Wing Loading - This is the amount of weight per square
foot that has to be overcome to provide lift. It is normally
expressed in ounces per square foot. This specification can
be easily calculated as follows: If you know the square
inches of the wing, simply divide by 144 to obtain square
feet. Divide the total weight (in ounces) of the airplane by
the wing area (in square feet). This information is valuable
when deciding on which airplane to build next. Planes with
high wing loading numbers must fly faster to stay in the air.
These are generally “performance” airplanes. Conversely,
planes with lower numbers do not need as much air flowing
around the wing to keep it flying. Gliders and trainer
airplanes fall into this category because slow, efficient flight
is desirable.
Wing Root - The centerline of the wing, where the left and
right wing panels are joined.
Yaw Axis - The airplane axis controlled by the rudder. Yaw
is illustrated by hanging the airplane level by a wire located
at the center of gravity. Left or right movement of the nose
is the Yaw movement.
Z-Bend - A simple Z-shaped bend in the wire end of a
pushrod, which is used to attach the pushrod to a servo
output arm.
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