What occurs if the overspeed governor fails?

When the overspeed governor fails, the Ng governor takes over the regulation of the engine speed. The Ng governor is designed to maintain the Ng (gas generator speed) within safe operational limits, ensuring the engine operates efficiently and preventing overspeed situations.

In the event of an overspeed governor failure, it is crucial that the system has a backup to manage engine speed effectively. The Ng governor's function as a control mechanism allows for the continued operation of the engine without an immediate shutdown or other detrimental effects. It provides an essential safety net that helps maintain engine performance and safety, thereby preventing complete engine failure or critical operational issues under overspeed conditions.

Other options may imply direct engine shutdown or activation of warning systems, but these are typically not the immediate response to an overspeed governor failure. Instead, the Ng governor's role is to take swift corrective actions to maintain engine operation within acceptable parameters.