continuous-flow oxygen system. A system of aviation breathing oxygen in which a metered amount of oxygen flows continuously into the mask. A rebreather-type mask is used with a continuous-flow system. The simplest form of continuous-flow oxygen systems regulates the flow by a calibrated orifice in the outlet to the mask, but most systems use either a manual or automatic regulator to vary the pressure across the orifice proportional to the altitude being flown.
continuous gusset (wing rib bracing). A brace made of thin plywood used to reinforce the glue joints of all the upright and diagonal braces used in a wooden wing rib. The continuous gusset runs the full length of the rib, rather than being made in the form of small separate gussets at each joint.
continuous-loop fire detection system. A type of fire detection system which uses two conductors, separated by a thermistor material, formed into a continuous loop that surrounds the area being protected.
A thermistor is an electrical insulator at normal temperature, but becomes a conductor when heated. When a fire occurs, the thermistor conducts electricity and completes the fire warning circuit. This turns on the fire warning light and starts the fire warning horn or bell.

continuous magnetic particle inspection. A method of magnetic particle inspection in which the part is inspected while the magnetizing current is flowing either through the material or through a coil, or solenoid around the part.

continuous wave radio transmission. See CW.
contour (meteorology). A line drawn on a constant-pressure chart to show the pattern of points of equal pressure. These lines are similar to the contours shown on a topographical relief map that show lines of equal height.
contour (radar meteorology). A line on a radar scope that shows the areas of equal radar echo intensity.
contouring circuit (radar meteorology). A circuit which displays multiple contours of echo intensity simultaneously on the plan position indicator or range-height indicator scope.
contour map. A map of a geographical area which has lines drawn on it that connect points of equal elevation.