Aviation Information Flashcards
Types of Aviation
Civil and military
Fixed Wing
Fighter jets, bombers, airliners, and corporate jets
Rotary Wing
Helicopters, gyrocopters, and tilt-rotor flying machines
Airfoil
A wing or helicopter blade that generates more lift than drag as air flows over its upper and lower surfaces. A propeller is also an airfoil. Airfoils are carefully designed and can be made of non-metallic materials such as composites.
Angle of Attack
The angle between the chord line of an airfoil and its direction of motion relative to the air (i.e. the relative wind). AOA is an aerodynamic angle.
Angle of Incidence
In the context of fixed-wing airplanes, the angle of incidence is the inclination of the wing or tail surface attached to the fuselage relative to an imaginary line that is parallel to the aircraft’s longitudinal axis.
Anhedral Angle
The downward angle of an airplane’s wings and tail plane from the horizontal is called the anhedral angle, or negative dihedral angle.
Attitude
An aircraft’s position relative to its three axes and a reference as such as the earth’s horizon.
Center of Gravity (CG)
An aircraft’s center of mass, the theoretical point through which the entire weight of the machine is assumed to be concentrated.
Chord
The distance between the leading and trailing edges along the chord line is an airfoil’s chord. In the case of a tapered airfoil, as viewed from above, the chord at its tip will be different than at its root. Average chord describes the average distance.
Chord Line
An imaginary straight line from the airfoil’s leading (front) edge to its trailing (aft) edge.
Constant Speed Propeller
A controllable-pitch propeller whose angle is automatically changed in flight by a governor in order to maintain a constant number of revolutions per minute (rpm) despite changing aerodynamic loads.
Controllability
A measure of an aircraft’s response relative to flight control inputs from the pilot via a control in the cockpit.
Controllable Pitch Propeller
A propeller that can be varied in terms of its blade angle by the pilot via a control in the cockpit.
Coordinated Flight
When the pilot applies fight and power control inputs to prevent slipping or skidding during any aircraft maneuver, the flight is said to be coordinated.
Critical Angle of Attack
The angle of attack at which an airfoil stalls (loses lift) regardless of the aircraft’s airspeed, attitude, or weight.
Dihedral Angle
The upward angle of an airplane’s wings and tail plane from the horizontal.
Dihedral Effect
The amount of roll movement produced per degree pf sideslip is called dihedral effect, which is crucial in terms of an aircraft’s rolling stability about its longitudinal axis.
Directional Stability
An aircraft’s initial tendency about its yaw (vertical) axis. When an aircraft is disturbed yaw-wise from its equilibrium state, for example, and returns to the state (i.e. aligned with the relative wind) because of the aerodynamic effect of the vertical stabilizer, it is said to be directionally stable.
Downwash
Air that is deflected perpendicular to an airfoil’s motion.
Drag Coefficient
A dimensionless quantity that represents the drag generated by an airfoil of a particular design.
Drag Curve
A constructed image of the amount of aircraft drag at different airspeeds.
Dynamic Stability
Describes the tendency of an aircraft after it has been disturbed from straight-and-level flight to restore the aircraft to its original condition of flying straight and level by developing corrective forces and moments.
Equilibirum
In the context of aviation, equilibrium is an aircraft’s state when all opposing forces acting on it are balanced, resulting in unaccelerated flight at a constant altitude.
Feathering Propeller
A controllable-pitch propeller that can be rotated sufficiently by the pilot (via a control lever in the cockpit connected to a governor in the propeller hub) so that the blade angle is parallel to the line of flight, thereby minimizing propeller drag.
Forward Slip
A pilot-controlled maneuver where the aircraft’s longitudinal axis is inclined to its flight path.
Glide Ratio
The ratio between altitude lost and distance traversed during non-powered flight (e.g. following an engine failure, in a sailplane).
Glidepath
An aircraft’s path’s across the ground while approaching to land.
Gross Weight
An aircraft’s total weight when it is fully loaded with aircrew, fuel, oil, passengers and/or cargo (if applicable), weapons, etc.
Gyroscopic Procession
The attribute of rotating bodies to manifest movement ninety degrees in the direction of rotation from the point where a force is applied to the spinning body.
Heading
The direction in which the aircraft’s nose is pointed.
Inertia
A body’s opposition to change in motion.
Internal Combustion Engine
A mechanical device that produces power from expanding hot gases created by burning a fuel-air mixture within the device.
Lateral Stability (Rolling)
An aircraft’s initial tendency relative to its longitudinal axis after being disturbed, its designed quality to return to level flight following a disturbance such as a gust that causes one of the aircraft’s wings to drop.
Lift Coefficient
A dimensionless quantity that represents the lift generated by an airfoil of a particular design.
Lift/Drag Ratio
A number that represents an airfoil’s efficiency, the ratio of the lift coefficient to the drag coefficient for a specific angle of attack.
Lift-Off
The act of rising from the earth as a result of airfoils lifting the aircraft above the ground.