Definition
A cockpit instrument that displays the temperature of the gases entering the turbine section of a turbine engine, measured by thermocouples placed at or just upstream of the first stage of turbine blades. Because the turbine inlet is the hottest point in the engine that can be practically monitored, TIT is used as the primary limit for engine power settings, and exceeding the published TIT limit even briefly can damage turbine components.
Plain English
A gauge that shows how hot the gas is just as it hits the spinning turbine blades inside a jet or turboprop engine. This is the hottest spot pilots can watch, and going over the red line can wreck the engine.
Context Anchor
Seen in turbine engine instrument discussions and during engine start, takeoff, climb, and high-power operation checks.
Derivation
‘Turbine’ comes from Latin turbo, meaning a spinning thing or whirlwind — fitting for the rapidly rotating blades the gas passes through. ‘Inlet’ simply means the entry point. So TIT literally measures the gas temperature at the entrance to the turbine — the first place the hot gas meets metal that has to survive it.
Why Pilots Care
Excessive TIT can damage turbine blades and reduce engine life; pilots use the gauge to stay within manufacturer limits and maintain safe engine operation.
Analogy
It is like watching a temperature gauge before a very heat-sensitive machine part, not after it. The pilot wants to know if the heat reaching that part is still within the safe range.
Intuition Check
Do not read “inlet” as the engine’s outside air intake here. In this term, the inlet is the entrance to the turbine section inside the engine.
Example Sentence 1
During engine start, the pilot watched the TIT gauge closely to make sure the temperature stayed below the start limit.
Example Sentence 2
After engine start the TIT gauge stabilized at a normal reading before the pilot advanced the power lever.