B737-800
Confusion; Training / Qualification
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown; Inflight Event / Encounter Fuel Issue
Aircraft Equipment Problem Dissipated; Flight Crew Became Reoriented; Flight Crew FLC complied w / Automation / Advisory
Company Policy; Manuals; Procedure
Fuel IMBAL light after takeoff; the 1;200 LB imbalance was corrected by the QRH procedure. This was entered in the logbook.We had an extended ground delay where we need to run the APU for cooling and per procedure for extended APU operation we positioned an AC pump on. And per procedure; because we were not in the cockpit for this delay; we could not run a center pump; the manual does not address how to avoid an imbalance in this particular situation. But most importantly; I will be more diligent about checking the distribution of the fuel before starting the engines and responding; 'checked' to 'Fuel Quantity and Distribution.' Note: The QRH procedure was followed; but it makes no mention of what to do if there is fuel in the center tank. This differs from the operating manual's Fuel Balancing procedure that has you turn off the center pumps.
During an extended ground delay with the APU running from a wing tank fuel pump; an imbalance developed below the IMBAL alert threshold. After takeoff IMBAL alerted and the crew then realized the Before Start Checklist was incorrectly completed and no procedure covered the ground APU fuel configuration.