What type of probe is commonly located before the first stage turbine wheel?

The temperature probe, specifically designed to measure Turbine Inlet Temperature (TIT), is crucial in assessing the performance and efficiency of a gas turbine engine. Located before the first stage turbine wheel, this probe provides vital data about the temperature of the gases entering the turbine. Monitoring the TIT is essential for engine operation as it influences both the combustion process and the turbine's mechanical integrity.

By ensuring that the turbine operates within the specified temperature limits, the probe helps to prevent overheating, which can lead to premature wear or catastrophic failure of engine components. Additionally, the TIT readings assist in optimizing fuel efficiency and performance tuning of the engine, making it a key parameter for both operation and maintenance.

In contrast, pressure probes measure the pressure of gases but are typically used in different stages of the engine, flow probes assess airflow rates and are also positioned differently, and fuel flow probes monitor the amount of fuel being supplied but do not operate within the turbine section. Thus, the temperature probe's specific function and placement in the turbine system underscore its importance in ensuring safe and efficient engine performance.