Which statement is true about the APU fuel supply?

Which statement is true about the APU fuel supply?

• A. It is drawn from the left collector tank
• B. It is drawn from the right collector tank
• C. It comes from the main fuel line
• D. It is prefilled from an external reservoir

Answer: (A)

Fuel to the APU comes from a dedicated left collector tank. Collector tanks gather fuel from the main tanks and feed specific systems through their own pumps. The left collector is assigned to the APU, so the APU’s fuel pump draws from that tank. This separation keeps the APU fuel supply independent from the engines and the main line, ensuring a reliable start and steady operation even when engines aren’t running. Using the right collector tank or pulling directly from the main line would mix feeds or compromise reliability, and an external reservoir isn’t used for normal APU operation.

Fuel to the APU comes from a dedicated left collector tank. Collector tanks gather fuel from the main tanks and feed specific systems through their own pumps. The left collector is assigned to the APU, so the APU’s fuel pump draws from that tank. This separation keeps the APU fuel supply independent from the engines and the main line, ensuring a reliable start and steady operation even when engines aren’t running. Using the right collector tank or pulling directly from the main line would mix feeds or compromise reliability, and an external reservoir isn’t used for normal APU operation.