Which statement accurately describes the number of idle power settings available from FADEC?

• A. There are four idle settings
• B. There are six idle settings
• C. There are five idle settings
• D. There are seven idle settings

Answer: (C)

FADEC controls idle by using multiple discrete power levels so the engine can hold a stable idle under different conditions. In this system, there are five idle power settings. This gives enough range to cover common operating scenarios—such as varying temperatures, altitudes, and accessory loads—without adding unnecessary complexity to the control logic. Four settings would be too few to reliably accommodate the typical variations, while six or seven would introduce more options than the design requires. Therefore, five idle settings is the right count.