The booster pump should be used for four things other than the event of an engine driven pump failure, what are they?

• A. Take off and landing
• B. Changing tanks
• C. Low flying
• D. All of the above

Answer: (D)

The booster pump is there to ensure a reliable fuel supply to the engine when the engine-driven pump isn’t providing the needed pressure or when a quick, positive feed is required. It’s not just about pump failure—it's used in several operational situations to prevent fuel starvation and to make fuel management smoother.

Using the booster pump during takeoff and landing helps maintain steady fuel pressure during periods of high power demand and critical phase flight, where any drop in pressure could affect engine performance. Changing tanks benefits from the booster pump because it purges air from the lines and ensures fuel is flowing from the new tank to the engine. Low-flying situations can risk fuel pressure due to changes in draw or line configuration, so the booster pump helps keep a positive feed as you operate closer to the fuel source and with varying attitudes.

These are all valid uses, and together they cover the typical duties of the booster pump beyond simply compensating for an engine-driven pump failure.