B757 flight crew and dispatcher reported errors in the flight release software when calculating for ...

Narrative:

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 pounds; minimum required fuel load for takeoff. The second is 3;000 pounds; minimum required on board for landing. Per the MEL; this 3;000 pounds is penalty fuel; i.e. Unusable. So; the way it seems to me; I must take off with at least 24;400 pounds; and I can't land with less than 3;000 pounds. I am allowed/legal and safe to burn below 24;400 pounds 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 pounds is wrong. It should be 21;843 pounds 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 pounds. 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 pounds. The MEL clearly states that 24;400 pounds 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.

Original NASA ASRS Text

Title: B757 flight crew and Dispatcher reported errors in the flight release software when calculating for a deferred fuel pump.

Narrative: 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.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1611704
Time
Date	201901
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Parked
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine Flight Crew Instrument
Person 2
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Instrument Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Events
Anomaly	Deviation - Procedural Published Material / Policy Deviation - Procedural Weight And Balance Inflight Event / Encounter Fuel Issue

B757 flight crew and dispatcher reported errors in the flight release software when calculating for a deferred fuel pump.