Definition
A number that describes how much the electrical resistance of a material changes for each one-degree change in its temperature. A positive coefficient means resistance rises as temperature rises; a negative coefficient means resistance falls as temperature rises.
Plain English
A figure that tells you how much a material's resistance to electrical current goes up or down when it gets hotter or colder.
Context Anchor
Seen in aircraft electrical, instrument, and temperature-sensing discussions, especially when a part’s resistance is used to measure or respond to temperature.
Derivation
Thermal comes from the Greek therme, meaning heat. Coefficient comes from Latin and means a multiplying factor. Together the term simply means 'the heat-related multiplier for resistance' -- the number you use to predict how resistance shifts with temperature.
Why Pilots Care
Prevents inaccurate resistance readings that could affect circuit performance in temperature extremes.
Grounding Statement
As an aircraft part warms up, its electrical resistance may rise or fall by a predictable amount.
Intuition Check
This does not mean resistance to heat. It means electrical resistance changing because of temperature.
Example Sentence 1
Most metals used in aircraft wiring have a positive thermal coefficient of resistance, so their resistance increases as the wire heats up under load.
Example Sentence 2
High temperatures in the engine compartment require accounting for the thermal coefficient of resistance to avoid false fault indications.