Key Terms in Aviation and Navigation

Lift

The force that's created by the effect of airflow as it passes over and under the wing.

Light-year

The distance that light travels in one year, about 6 trillion miles.

Longitude

Longitude is a coordinate that is used to specify positions on a sphere. The longitude of a place is the distance of the place to the prime meridian, measured in degrees along a circle at a fixed distance to the poles of the sphere.

Longitudinal distance

A straight line parallel to the length of the fuselage but that runs through the aircraft's center of gravity.

LORAN

Long Range Navigation. An electronic navigational system by which hyperbolic lines of position are determined by measuring the difference in the time of reception of synchronized pulse signals from two fixed transmitters.

Low Earth Orbit

Abbreviated as LEO. Orbits which are relatively close to the Earth.

Machinability

The way a material responds to specific machining techniques.

Magnetic Course

Course of a vessel in relation to magnetic north.

Magnetic Deviation

Amount by which a ship's magnetic compass needle points to one side or the other of magnetic north.

Magnetic Variation

A compass "error" resulting from the fact that at most points on the Earth's surface the direction of the magnetic lines of force is not toward the geographic North Pole or South Pole.

Manueverability

Characteristic of the aircraft that permits you to maneuver it easily and allows it to withstand the stress resulting from the maneuver.

Metacognition

The mental process that learners use to understand and monitor their own thinking.

Stiffness

The ability of a material to resist deflection or stretching.

Molniya Elasticity

Abbreviated as Moly. A highly inclined, highly elliptical orbit.

Roll

Rolling motion about the longitudinal axis caused by ailerons deflecting in opposite directions and controlled by twisting the yoke.

RNAV

Area Navigation (RNAV) provides enhanced navigational capability to the pilot.

Thrust

Forward-acting force which opposes drag and propels the aircraft through the air.

Rudder

A rear vertical stabilizer that controls side-to-side or yawing motion of the aircraft nose.

Satellite

A small body which orbits a larger one. A natural or an artificial moon.

Scale Mode

A representation or copy of an object that is larger or smaller than the actual size of the object being represented.

Semi-Major Axis

Abbreviated as a. Describes the size of the ellipse.

Sensor

A device that responds to a physical stimulus (as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control).

Servo Motor

Any motor that is modified to give feedback concerning the motor's speed, direction of rotation, and number of revolutions.

Sextant

A sextant is a tool for measuring the angular altitude of a star above the horizon.

Stability

Aircraft stability is the characteristic of an airplane in flight that causes it to return to a condition of equilibrium, or steady flight, after it is disturbed.

Stall

Caused by the separation of airflow from the wing's upper surface resulting in a rapid decrease in lift.

Static Equilibrium

A condition where there are no net external forces acting upon a particle or rigid body and the body remains at rest or continues at a constant velocity.

Static Stability

Forces and moments on the body caused by a disturbance tend initially to return the body toward its equilibrium position.

Rod

Any of the long rod-shaped photosensitive receptors in the retina that are responsive to faint light.

Strain

Change in the length of an object in some direction per unit.

Gas Turbine

A device that creates a hot exhaust gas which was passed through a nozzle to produce thrust.

Tubofan

A turbojet engine that has a large ducted fan mounted on the shaft ahead of the compressor.

Subsonic

Aircraft speeds under Mach 1.

Supersonic

Aircraft speeds between Mach 1 and 5.