View the SAFE™ Glossary

Found on the trailing edge of each wing, they work in opposite directions to bank (roll) the airplane about the longitudinal axis. To roll right, the right aileron is raised and the left aileron lowers.
AS3X® technology
The AS3X system for airplanes is an exclusive electronic and setup enhancement that combines multi-axis sensors and state-of-the-art software that helps make flight smoother and more stable. It is available in some RTF aircraft or as an add-on component a modeler can choose to improve the flight characteristics of their airplane.
The axes of an aircraft are three imaginary lines that pass through an aircraft's center of gravity. The axes can be considered as imaginary axles around which the aircraft rotates. The three axes pass through the center of gravity at 90° angles to each other. The axis that extends nose through tail is called the longitudinal axis, and rotation about this axis is called roll. The axis that extends wingtip through wingtip is called the lateral axis, and rotation about this axis is called pitch. The axis that passes vertically is called the vertical axis, and rotation about this axis is called yaw.
A term used to describe the tilt of an aircraft longitudinally (roll) that occurs while turning. An angle of bank determines the rate of turn as well as the stability of the aircraft in that turn.
Buddy Box
The setup of two transmitters, linked by cable, for the purpose of RC flight instruction. The instructor holds the primary transmitter and has authority to transfer control to the secondary transmitter in the hands of the student (buddy) or resume control instantly.
Center of Gravity (CG)
The point at which an airplane would balance if it were possible to suspend it at that point. It is the mass center of the airplane, or the theoretical point at which the entire weight of the airplane is assumed to be concentrated. The location depends on the distribution of weight in the airplane.
Control Surfaces
These are the moving portions of the wing, stabilizer and fin of an aircraft that are named aileron, elevator, and rudder controls respectively. These primary controls allow the pilot to roll (aileron), pitch (elevator) and yaw (rudder) the aircraft. Secondary controls include flaps and spoilers.
The net aerodynamic force parallel to the relative wind, usually the sum of two components: induced drag and parasitic drag.
Dual Rates
A two or three-position switch on the transmitter which can be set to select different control throws for flight controls. They are used so that the pilot can increase or decrease the maneuverability of the aircraft in flight.
The horizontal, movable primary control surface in the tail section, or empennage, of an airplane. The elevator is hinged to the trailing edge of the fixed horizontal stabilizer and is the primary control for pointing the nose up or down about the lateral axis.
The vertical surface of the tail that gives the airplane stability while in flight. The yaw control surface connected to it is called the rudder.
Hinged portion of the trailing edge between the ailerons and fuselage. In some aircraft, ailerons and flaps are interconnected to produce full-span "flaperons". In either case, flaps change the lift and drag on the wing.
The point during landing in which the pilot reduces airspeed while raising the nose of the airplane with up elevator which further slows the descent of the aircraft and makes the touchdown as smooth as possible.
Flight Envelope
Ranges of maneuverability where limits of roll, pitch and yaw attitude are set in order to protect the stability of an aircraft.
Gimbal (or Stick)
The device that allows the user to input desired control movements into the transmitter.
Landing Gear
The wheel assembly an aircraft uses to land and maneuver on the ground
A component of the total aerodynamic force on an airfoil and acts perpendicular to the relative wind.
Motion of the aircraft about the lateral axis where the nose of the aircraft points up or down conventionally by moving the elevator on the tail.
The ability to incrementally adjust aircraft control positions and input.
The receiver unit in the airplane receives the signals from your transmitter and passes your instructions along to the electronic devices connected to the controls.
Relative Airflow (also Relative Wind)
Direction of the airflow produced by an object moving through the air. The relative wind for an airplane in flight flows in a direction parallel with and opposite to the direction of flight; therefore, the actual flight path of the airplane determines the direction of the relative wind.
An assembly of rotating airfoils, as that of a helicopter mounted horizontally to add lift, and on its tail mounted vertically to add rotational stability.
The movable primary control surface mounted on the trailing edge of the vertical fin of an airplane. Movement of the rudder rotates the airplane about its vertical axis.
SAFE™ Technology
SAFE (Sensor Assisted Flight Envelope) technology is a revolutionary electronic flight envelope protection system. It also offers smoother flight capability that battles windy conditions for you and multiple modes so you can fly with the level of protection and assistance that suits any given moment of the flight.
A servo transforms your command delivered by the transmitter to the receiver into physical movement of a control surface on the aircraft.
Spatial awareness
The ability to be aware of oneself in space. Aircraft with SAFE technology use this awareness to help the RC pilot maintain control within a specific flight envelope.
A fixed horizontal or vertical surface on the tail that gives the airplane stability while in flight. The horizontal surface is often referred to as the "stab" and the vertical stabilizer is popularly called the "fin".
A rapid decrease in lift caused by the separation of airflow from the wing's surface, brought on by exceeding the critical angle of attack. A stall can occur at any pitch attitude or airspeed.
A control of the engine or electric motor that increases or decreases the speed of propulsion system and the amount of thrust produced.
The forward aerodynamic force produced by a propeller, fan, or turbojet engine as it forces a mass of air to the rear, behind the aircraft.
(1) A resistance to turning or twisting. (2) Forces that produce a twisting or rotating motion. (3) In an airplane, the tendency of the aircraft to turn (roll) in the opposite direction of rotation of the engine and propeller. (4) In helicopters with a single, main rotor system, the tendency of the helicopter to turn in the opposite direction of the main rotor rotation.
Wing Area
The total surface of the wing (measured in square inch and square decimeters for model aircraft), which includes control surfaces and may include wing area covered by the fuselage (main body of the airplane), and engine nacelles.
Wing Chord
The chord of an airplane wing is the straight line distance from the leading edge of a wing to the trailing edge at a given point along its span.
Wing Span
The maximum distance from wingtip to wingtip.
Rotation about the vertical axis, controlled by the rudder of an airplane. Moving the rudder left yaws the nose of the aircraft left, and vice versa.