What function do overheat sensors serve in a thermal anti-ice system operated by engine bleed air?

Overheat sensors in a thermal anti-ice system are critical for ensuring safe operation by monitoring temperature levels within the system. When these sensors detect temperatures that exceed predetermined limits, they trigger a response to protect the system and the aircraft from potential damage. Specifically, they send a signal to the anti-icing valves to close, thereby shutting off the flow of hot air from the engine bleed air system. This action prevents overheating, which could lead to component failure or other malfunctions.

This function is particularly important because the thermal anti-ice system relies on hot engine bleed air to prevent ice from forming on critical surfaces, such as wings and engine inlets. If the system were to overheat without appropriate responses, it could compromise the aircraft’s performance and safety. Thus, overheat sensors play a vital role in the overall effectiveness and safety of the thermal anti-ice system by ensuring that the hot air supply is managed appropriately based on temperature conditions.