What function does the X-BP 1-2 push button perform on the fuel panel?

The X-BP 1-2 push button on the fuel panel is designed to supply fuel from an alternate tank. This functionality is critical in managing fuel sources during flight operations, particularly when ensuring adequate fuel is available for the engines. In situations where the primary fuel source might be depleted or compromised, engaging this button allows the aircraft to draw fuel from a secondary tank, ensuring continuous operation and enhancing safety.

While cross-feed fueling is important, it specifically involves allowing fuel to flow from one tank to another rather than selecting an alternate tank as a source. Maintaining fuel pressure is managed by different systems that monitor and regulate the pressure throughout the fuel system, and the ability to turn off the fuel supply is controlled by separate valves and switches. Thus, the functionality of the X-BP 1-2 push button is focused specifically on accessing fuel from an alternate tank.