Under what condition is "Propeller Feathering?" executed?

The execution of "propeller feathering" is primarily conducted in response to an engine failure. This procedure is vital for reducing drag that occurs when one of the engines is inoperative. By adjusting the pitch of the propeller blades to a nearly vertical position, drag is minimized, allowing the aircraft to maintain better performance and control during a critical phase of flight following engine failure.

This action helps ensure that the aircraft can either maintain altitude as necessary or facilitate a controlled descent, enhancing safety and efficiency of the aircraft's response to an emergency situation. Other scenarios such as takeoff, turbulence, or landing approaches do not involve propeller feathering since the engines are expected to operate normally at those times.