In the event of an engine failure and loss of oil pressure, what position does the propeller revert to?

When there is an engine failure and subsequent loss of oil pressure, the propeller typically reverts to a feathered position. This position minimizes drag on the aircraft, which is critical during an emergency situation such as an engine failure. Feathering the propeller effectively aligns the blades with the directional flow of air, thereby reducing resistance and allowing the aircraft to maintain gliding capability.

In scenarios involving multi-engine aircraft, feathering is particularly important as it helps the pilot control the aircraft's performance and configuration after one engine has failed. It enhances the aircraft's glide performance and allows for a more effective emergency landing.

The other positions mentioned, such as low pitch, high pitch, and idle, would not reduce drag as effectively as feathering and could potentially lead to greater control challenges during an engine-out situation. Thus, reverting to feather is the most beneficial and safety-oriented response in the event of engine failure and loss of oil pressure.