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

C

Cabin altitude

Cabin pressure in terms of equivalent altitude above sea level.

Cage

The black markings on the ball instrument indicating its neutral position.

Calibrated

The instrument indication compared with a standard value to determine the accuracy of the instrument.

Calibrated airspeed

The speed at which the aircraft is moving through the air, found by correcting IAS for instrument and position errors.

Camber

The camber of an airfoil is the characteristic curve of its upper and lower surfaces. The upper camber is more pronounced, while the lower camber is comparatively flat. This causes the velocity of the airflow immediately above the wing to be much higher than that below the wing.

Canard

A horizontal surface mounted ahead of the main wing to provide longitudinal stability and control. It may be a fixed, movable, or variable geometry surface, with or without control surfaces.

Canard configuration

A configuration in which the span of the forward wings is substantially less than that of the main wing.

Cantilever

A wing designed to carry loads without external struts.

CAS

Calibrated airspeed

CDI

Course deviation indicator.

Ceiling

The height above the earth’s surface of the lowest layer of clouds, which is reported as broken or overcast, or the vertical visibility into an obscuration.

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. It may be expressed in inches from the reference datum, or in percentage of mean aerodynamic chord (MAC). The location depends on the distribution of weight in the airplane

Center of gravity limits

The specified forward and aft points within which the CG must be located during flight. These limits are indicated on pertinent airplane specifications.

Center of gravity range

The distance between the forward and aft CG limits indicated on pertinent airplane specifications.

Center of pressure

A point along the wing chord line where lift is considered to be concentrated. For this reason, the center of pressure is commonly referred to as the center of lift.