General Authority of Civil Aviation (GACA) Aeronautical Information Publication (AIP) Practice Exam

What does the EEC provide to protect against overspeed?

1. N1 and N2 red line overspeed protection

2. Fuel cutoff mechanism

3. Throttle position feedback

4. Visual indicators in cockpit

The correct answer is: N1 and N2 red line overspeed protection

The EEC, or Electronic Engine Control, is responsible for monitoring and managing engine performance parameters, including rotational speeds of the engine's high-pressure and low-pressure compressors, represented as N1 and N2. By providing red line overspeed protection, the EEC ensures that the engine does not exceed these critical speed limits. This is crucial because overspeed conditions can lead to mechanical failures or catastrophic damage to the engine. The EEC achieves this through real-time data monitoring and control actions that adjust fuel flow or throttle input when speeds approach predetermined red line limits. This form of protection is fundamental in maintaining safe engine operation, preventing the risks associated with overspeed. Other options, while relevant to overall engine health and performance, do not specifically address overspeed protection in the same direct manner. For instance, a fuel cutoff mechanism is typically a safety feature to halt fuel flow in emergencies, throttle position feedback helps in monitoring engine response, and visual indicators in the cockpit assist pilots in situational awareness, but none provide the same proactive protective measures against overspeed as the red line protection feature does.