RC: Remote Control
Receiver: Much like your car radio, the receiver gets radio waves sent through the air. These waves contain instructions for the servos that move the rc airplane's controls. Also called an "RX"
Transmitter: This is the box with joysticks that you hold, and use to send commands to the rc airplane. Also called a "TX"
Servo: Each servo (metal or nylon) is a small motor that is wired to the receiver. If given instructions to do so by the transmitter, the servo moves a certain amount, which also moves the aircraft control surface that is mechanically connected to it.
Servo arm: Connects the servo motor to the pushrod
Brushless motor: type of electric motor used in rc electric aircraft. Brushless motors are much more powerful than traditional brushed motors, and are fast becoming the norm. They can be inrunner or outrunner motors. More details here.
Pushrod: Connects the servo arm to the control horn
Control Horn: Connects the pushrod to the control surface or device, eg: rudder, elevator, aileron, throttle, speed control
Rudder: The movable part at the back of the vertical fin. Causes the airplane to rotate left or right (yaw) about a vertical axis.
Elevator: The movable part at the back of the horizontal stab. Causes the airplane to rotate up or down (pitch) about a horizontal axis.
Aileron: The movable part at the back of the wing. Causes the airplane to roll left or right.
Vertical Fin: Part of the airplane's tail piece. Stabilizes the aircraft against yawing motions.
Aerobatic: Any maneuver or series of maneuvers that involve stunts of any kind, such as loops, rolls and spins. An airplane that is capable of performing such stunts is said to be "fully aerobatic".
Airfoil: The cross-section shape of a wing. Airfoils can be flat-bottomed, semi-symmetrical or symmetrical, depending on the style of airplane and what it needs to do. Also written as aerofoil, depending on which country you are in.
Angle of Attack: The angle of the wing (when viewed from the end) in relation to the horizontal airflow when the airplane is flying. Nothing to do with your incoming trajectory when trying to cut the tail off your friend's model in aerial combat games.
ARF / ARTF: Almost Ready To Fly. This one's a legitimate abbreviation. An ARF model airplane needs a few small finishing touches and you have to install the engine and radio gear yourself. They vary in degrees of completeness, from manufacturer to manufacturer. More details here.
Barrel roll: An aerobatic maneuver that involves the airplane following the twist of a large imaginary corkscrew (horizontal) through the air.
Bind-N-Fly (BNF): A trademark name for a range of Horizon Hobby distributed aircraft (namely ParkZone & E-flite) whereby the model is sold in RTF form but lacks the transmitter. A DSM2 compatible receiver is included though so you just, er, bind and fly. More details here.
Buddy Box: One of the best training aids, where the student's transmitter is attached via cable to the instructor's. The student has complete control over the model, but at the flick of a switch the instructor can take control if the student gets into difficulties. Or just to be mean, funny or annoying.
Center of Gravity / CG: The airplane's point of fore-aft balance. As a very general rule of thumb it's found approximately 1/4 to 1/3 of the way back from the leading edge of the wing and is built in during the design stage. More details here.
Control surface: The term used to describe the moving part of any flying surface ie rudder, elevator and ailerons are all control surfaces. More details here.
Elevons: When elevator and aileron control is made by the same control surface, this surface is called an elevon(s). Only possible with a mixing facility on the rc set.
Flaps: Moving sections of the trailing edge of the wing, usually found between the ailerons and fuselage. Used to create more lift at slower flying speeds and also to slow the plane on landing approach, flaps are usually only found on rc airplanes with 5 or more channels.
Flaperons - a single control surface on the trailing edge of each wing that does the job of flaps and ailerons. An rc system with control mixing capability is needed to have flaperons.
Fuselage - the main body of an airplane, excluding wings, tail and everything else. Flying wings, oddly enough, don't have much in the way of a fuselage.
Horizontal stabiliser - also called the tailplane. The horizontal surface at the back of the fuselage, to which the elevators are attached.
Leading edge - the front edge of the wing, tailplane or rudder.
Lift - the force created by the forward motion of the airplane's wing or helicopter's rotor blades. Air pressure over the wing is less than the pressure below the wing and so the wing, along with the rest of the model, is pushed upwards.
Li-Po - stands for lithium ion polymer battery. These are the most modern kind of battery pack being used in electric aircraft. They provide enormous amounts of power for their size, especially when used in conjunction with a brushless motor.
Mode 2 - refers to the set-up of the transmitter whereby the left stick operates the throttle and rudder, and the right stick operates the elevator and ailerons. Common in North America and much of the world. More details here.
Outrunner - the other type of brushless motor, where the outer casing, or 'can', of the motor rotates with the shaft and permanent magnets, which are attached to the inside of the can. Outrunners produce more torque, so they are more powerful than inrunners and are rarely geared.
Plug-N-Play (PNP) - Ready To Fly models that are missing the transmitter and receiver, allowing the pilot to use his/her own.
Retracts - abbreviation for 'retractable undercarriage', which is an undercarriage that folds up into the airplane's wings or fuselage after take off. They work most of the time, but sometimes they decide not to re-appear just when you need them the most.
RTF - Ready To Fly. RTF models can be assembled in minutes, usually it's a case of just strapping on the wing.
RTFs are very popular these days.
Rx - abbreviation for receiver.
Wing loading - a calculation that is useful when determining certain flight performance characteristics of a plane, the figure is obtained by dividing the flying weight of the airplane by the total wing area. A plane with large wings relative to its weight will have a lower wing loading, which means better lifting capacity but not so great high speed performance, and vice versa. Wing loading values are given in Oz/sq.ft (ounces per square foot).
