During which phase of flight must the fuel XFER PBA be selected closed?

Selecting the fuel XFER PBA (Push Button/ Switch) to the closed position during the takeoff phase of flight is essential for ensuring the aircraft operates safely and efficiently. During takeoff, maintaining appropriate fuel flow and balance is critical due to the high thrust demands and increased engine performance required. Having the fuel transfer system disengaged prevents any unexpected fuel movement that could affect the aircraft’s center of gravity or cause an imbalance, which is particularly important when the aircraft is most vulnerable.

In contrast, during climb, descent, or landing phases, while fuel management is still important, the operational pressures during takeoff necessitate that the fuel XFER feature be closed to assure stability and control. This cautious approach is standard operating procedure to mitigate risks associated with fuel transfers that could inadvertently affect performance during these critical phases of flight.