Aviation Maintenance Terms beginning with R

Radiant energy

Electromagnetic waves of certain frequencies produce heat when they are absorbed by the bodies they strike such as x-rays, light rays, and infrared rays

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Radiation

The continuous emission of energy from the surface of all bodies.

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Radical sign

The symbol √, used to indicate the root of a number.

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Radiographic inspection

Inspection using radiography to locate defects or flaws in airframe structures or engines with little or no disassembly.

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Radius (circle)

Equal to one-half the diameter of a circle.

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Ratio

The comparison of two numbers or quantities.

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Reamers

Tools made of either carbon tool steel or high- speed steel that are used to smooth and enlarge holes to exact size.

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Rectifier

A device for converting alternating current to direct current.

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Relative humidity

The ratio of the amount of water vapor actually present in the atmosphere to the amount that would be present if the air were saturated at the prevailing temperature and pressure.

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Remainder

The leftover number in the process of division.

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Repair

The restoration of an aircraft component to its previous state.

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Repair station

A maintenance facility certificated under 14 CFR part 145 to perform maintenance functions.

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Resistance

The opposition a device or material offers to the flow or current.

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Resonance

The increase in amplitude of vibrations of an electric or mechanical system exposed to a periodic force whose frequency is equal or very close to the natural frequency of the system.

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Retentivity

The ability of a material to hold its magnetism after the magnetizing field has been removed.

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Rheostat

A variable resistor used to vary the amount of current flowing in a circuit.

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Root

A number that when multiplied by itself a specified number of times will produce a given number. The two most commonly used roots are the square root and the cube root.

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Routine inspection

A visual examination or check of an item in which no disassembly is required

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