Definition
A cockpit instrument that displays the temperature of the air inside the carburetor intake, used by the pilot to detect conditions favorable to carburetor icing and to verify the effect of carburetor heat.
Plain English
A small gauge in the cockpit that shows how warm or cold the air is inside the carburetor, so the pilot can spot icing risk and check that carb heat is working.
Context Anchor
Seen in airplanes with carbureted engines, especially during engine operation in cool, damp air or when using carburetor heat.
Derivation
“Carburetor” comes from older words connected with mixing fuel vapor with air for burning in an engine. “Gauge” means an instrument used to measure something. The term names an instrument that measures air temperature at the carburetor.
Why Pilots Care
Early indication of icing risk allows timely use of carburetor heat to maintain engine power and avoid sudden roughness or failure.
Grounding Statement
If the air near the carburetor is in the icing range, ice can form there even when the outside air temperature is above freezing.
Intuition Check
Do not assume this gauge shows outside air temperature. It shows the temperature at or near the carburetor, where fuel evaporation and airflow can make ice possible.
Example Sentence 1
The pilot glanced at the carburetor air temperature gauge and saw the needle in the icing range, so he applied carb heat.
Example Sentence 2
During the preflight inspection the instructor confirmed the carburetor air temperature gauge needle moved smoothly through its full range.