Glossary

This glossary contains information on terms, phrases and abbreviations used by the Aviation industry. While this list does not include all aviation terminology, it is the purpose of this glossary to aid the general viewer in better understanding aviation terms as it pertains to content on this website. A full list of aviation terminology can be found here.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

R

Restricted area.

Airspace designated under 14 CFR part 73 within which the flight of aircraft, while not wholly prohibited, is subject to restriction.

Reverse sensing.

The VOR needle appearing to indicate the reverse of normal operation.

RF.

Radio frequency.

Rhodopsin.

The photosensitive pigments that initiate the visual response in the rods of the eye.

Rigging.

The final adjustment and alignment of an aircraft and its flight control system that provides the proper aerodynamic characteristics.

Rigidity in space.

The principle that a wheel with a heavily weighted rim spinning rapidly will remain in a fixed position in the plane in which it is spinning.

Rigidity.

The characteristic of a gyroscope that prevents its axis of rotation tilting as the Earth rotates.

Rime ice.

Rough, milky, opaque ice formed by the instantaneous freezing of small supercooled water droplets.

Risk elements.

There are four fundamental risk elements in aviation: the pilot, the aircraft, the environment, and the type of operation that comprise any given aviation situation.

Risk management.

The part of the decision-making process which relies on situational awareness, problem recognition, and good judgment to reduce risks associated with each flight.

Risk.

The future impact of a hazard that is not eliminated or controlled.

RMI.

See radio magnetic indicator.

RNAV.

See area navigation.

RNP.

See required navigation performance.

RT.

See receiver-transmitter.