B757-200
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Confusion; Communication Breakdown
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Fuel Issue
General None Reported / Taken
Company Policy; Human Factors; Procedure
Last week; I flew to ZZZ. We had an inop left aft fuel pump deferred (MEL attached). There are two important fuel numbers dealing with this; per the MEL. The first is 24;400 LBS; minimum required fuel load for takeoff. The second is 3;000 LBS; minimum required on board for landing. Per the MEL; this 3;000 LBS is penalty fuel; i.e. unusable. So; the way it seems to me; I must take off with at least 24;400 LBS; and I can't land with less than 3;000 LBS. I am allowed/legal and safe to burn below 24;400 LBS fuel on board. I believe my release (attached) had two mistakes on it. The first one I noticed was FOD (Fuel Over Destination.) The 6;743 LBS is wrong. It should be 21;843 LBS per the [flight manual] (FOB minus Burn (Dest+Taxi)). The Dispatcher (software) also subtracted the Adj (12;100) and the MEL (3;000) to arrive at 6;743 LBS. FOD is a planning tool for me to know if/when I need to divert and also to know if I have a fuel leak. The Adjust fuel (12;100) is usable if I need it. 6;743 is a meaningless number. The second error is the RQR of 23;195 LBS. The MEL clearly states that 24;400 LBS is the minimum fuel required for takeoff. I don't know if this error was caused by human input or a software/programming problem. Research by our Standards people will hopefully lead to education on the MEL and changes to the Flight Release software.
It is believed that the dispatcher had incorrectly notated the wrong FOD (Fuel Over Destination.) Per a deferral the flight was required to have extra fuel for departure which was in fact on board however it's believed the FOD was inaccurate. Believe the dispatcher made an error on the paperwork. Very well could have been a math error. To eliminate guess work. When this happens again in the future with the same MEL. It is required to discuss the fuel scenario with the dispatcher. To make sure all involved are on the same page.
B757 flight crew and Dispatcher reported errors in the flight release software when calculating for a deferred fuel pump.