How are probes and sensors heated on the 737-800?

In the Boeing 737-800, pitot probes and temperature probes are both heated electrically to ensure accurate readings in various weather conditions. The heating is crucial because it prevents ice formation on these critical instruments, which could otherwise lead to erroneous measurements of airspeed and temperature.

Electric heating is employed for these probes since it offers a reliable way to maintain their functionality even in freezing conditions. The pitot probes measure the dynamic pressure of the atmosphere to determine airspeed, while the temperature probes are essential for accurately measuring outside air temperature, both of which are vital for safe and effective flight operations.

This design choice is part of the overall aircraft systems' redundancy and safety measures, ensuring that pilots receive accurate data necessary for navigation and control, especially during takeoffs, landings, and flight through clouds or turbulent weather where icing could occur.