What is the purpose of the pump crossfeed valve?

The pump crossfeed valve's primary function is to facilitate the operation of the engines from a single fuel tank, allowing for fuel supply continuity even when one tank becomes depleted or if there is a malfunction in fuel system components. This capability is crucial for maintaining aircraft performance and safety during flight, especially in scenarios where one fuel tank may be unavailable for any reason.

By enabling the crossfeed of fuel, the valve helps to ensure that both engines can continue operating efficiently without being limited by the fuel status of individual tanks. This is especially significant in multi-engine aircraft where engine reliability and fuel management are critical for overall operational integrity.

In this context, it’s important to note that while the pump crossfeed valve contributes to overall fuel management and can affect fuel balance indirectly, its main purpose remains focused on allowing engines to operate from a single tank, ensuring that fuel supply isn’t interrupted due to tank isolation.