If an engine is shutdown by the over-speed protection system, the other engines' over-speed protection systems will be ___.

• A. Activated
• B. Remain Active
• C. Deactivated
• D. Fail Safe

Answer: (C)

Overspeed protection is an engine-specific safety feature, designed to protect each engine individually. If one engine is shut down by its overspeed protection, the control logic isolates that event to the affected engine. In that scenario, the protections on the other engines are deactivated to prevent cascading trips and to allow the remaining engines to be managed by the pilot without automatic shutdowns triggered by the single overspeed event.

So, the other engines’ overspeed protection systems being deactivated means they won’t automatically trip due to the disturbance that caused the first engine to shut down. Activating them or keeping them active would risk unnecessary shutdowns for the other engines, and “fail safe” isn’t the typical state described for this situation.