If the overspeed governor fails while the primary governor is operating, what will happen?

When the overspeed governor fails while the primary governor is still operational, the primary governor will maintain control over the propeller's RPM within its designated range. In this situation, the primary governor is designed to prevent the propeller from exceeding a specified RPM threshold. Therefore, with the primary governor functioning, the propeller's RPM will stabilize within the range of 1600 to 2000 RPM.

The role of the overspeed governor is primarily to act as a safety mechanism that limits the maximum RPM of the propeller, especially in the event that the primary governor fails. If the overspeed governor is not functioning but the primary system is still able to control the propeller's RPM effectively, the propeller's speed will not exceed the operational limits set by the primary governor. Hence, propeller RPM will remain consistently within the operational limits established by the primary governor.

The failure of the overspeed governor does not compromise the primary governor's ability to manage RPM within these parameters, leading to a controlled environment where the propeller does not experience an excessive increase in RPM under normal operating conditions.