How do you manually transfer fuel?

• A. Set X FLOW AUTO OVERRIDE to MAN, then select XFLOW on the low side to ON.
• B. Set X FLOW AUTO OVERRIDE to OFF, then disable XFLOW.
• C. Always leave XFLOW in AUTO and press START.
• D. Turn off fuel pumps and perform manual switch.

Answer: (A)

Manual control of the crossflow system is what allows fuel to move between tanks on demand. To transfer fuel manually, you first take the crossflow out of automatic operation by setting the crossflow AUTO OVERRIDE to MAN. This step hands control to you rather than letting the system decide when to crossflow. Then you enable the crossflow path on the low side by turning XFLOW ON for the low side valve. This opens the crossflow path so fuel can flow from the other tank into the low-side tank, accomplishing the transfer as directed by procedures. Other options don’t initiate a manual transfer: leaving automatic control active won’t start manual crossflow, turning off XFLOW prevents crossflow entirely, and simply starting or turning off pumps without engaging the crossflow path won’t accomplish the needed transfer.