Where does fuel to operate the APU come from?

• A. The left collector tank via a dedicated APU fuel pump
• B. The right collector tank via a shared pump
• C. The center tank via the crossfeed line
• D. External ground supply

Answer: (A)

Fuel for the APU is drawn from the left collector tank and delivered by a dedicated APU fuel pump. This setup keeps the APU’s fuel supply independent from the engines and from the right-side system, providing a reliable and clean supply specifically for start and operation. The other routes—via the center tank or through a crossfeed line—are associated with main-engine fuel distribution, not the APU, and external ground power doesn’t provide fuel to the APU. Using a dedicated pump from the left tank also helps maintain proper fuel pressure and prevents unintended crossfeed or imbalance issues during APU operation.