Definition
The temperature of the exhaust gases as they leave the engine's cylinders, measured by a probe in the exhaust system. EGT reflects how completely and efficiently the fuel-air mixture is burning and is used by the pilot to lean the mixture for the most efficient power setting in cruise.
Plain English
How hot the exhaust gases are coming out of the engine. Pilots watch this gauge to fine-tune how much fuel the engine is using.
Context Anchor
Seen on engine instruments and in heat-management discussions, especially when adjusting mixture, climbing, or operating an engine under high power.
Derivation
Exhaust comes from an older word meaning to draw out or empty. That fits the engine meaning: exhaust gas is the used-up gas being pushed out of the engine after burning.
Why Pilots Care
Monitoring EGT helps optimize fuel mixture for efficiency, detect detonation or valve issues early, and prevent engine damage.
Intuition Check
EGT is not the temperature of the engine metal itself. It is the temperature of the hot gases leaving the engine after the fuel-air mixture burns.
Example Sentence 1
During cruise, the pilot slowly leaned the mixture and watched the EGT rise until it peaked, then enriched slightly to the recommended setting.
Example Sentence 2
Rising EGT during climb prompted the pilot to open the cowl flaps for additional cooling.