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

When does the EEC select minimum idle?

1. During descent

2. As a function of flaps position and other conditions

3. Automatically at high altitude

4. During engine startup

The correct answer is: As a function of flaps position and other conditions

The selection of minimum idle by the Electronic Engine Control (EEC) is primarily linked to aircraft configuration, which includes factors such as flap position, engine temperature, and overall operating conditions. The EEC is designed to optimize engine performance and efficiency by determining the appropriate idle thrust setting that varies based on these operational parameters. For example, when flaps are extended during approach and landing, the aircraft's aerodynamic characteristics change, requiring adjustments in engine thrust to maintain the desired speed and control. The EEC takes these variables into account, allowing it to automatically select the minimum idle thrust necessary to support safe operation based on the current flight phase and condition. This dynamic adjustment plays a crucial role in enhancing the aircraft's performance, ensuring effective power management during critical flight regimes, especially when descending or preparing for landing. The other options do not accurately reflect the conditions under which the EEC selects minimum idle. For instance, while engine startup is a critical period, the selection process is not contingent upon static parameters but is instead responsiveness to changing flight dynamics.