Narrative:

In accordance with supplemental operating procedure message, center tank fuel pumps secured 1000 pounds. No fuel scavenged out during the next 2 hours. Arrived with about 5.6 per main tank. Entered in logbook. After talk with ZZZ1, determined supplemental operating procedure message in flight plan stating 1000 pounds remaining is usable and will scavenge 400 pounds per hour same as B767 is inaccurate. Maintenance check for scavenge pump allows minimum of 200 pounds per 1 hour 45 mins and they believe scavenging only starts less than 6000 pounds left main tank. After verifying scavenging pump operation, we continued flight adding 1000 pounds to release fuel to comply with our perceived intent of the airworthiness directive. With such a low acceptable scavenge pump output, I feel 1000 pounds remaining in center tank must be considered unusable ballast and reflected as such in the supplemental operating procedure messages and fuel sheet. Captain should not be asked to sign flight plan with known erroneous supplemental operating procedure messages and which has inaccurate fuel burn/usage calculations.

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Original NASA ASRS Text

Title: A B757-200 WAS DISPATCHED AND OPERATED IN NON COMPLIANCE WITH THE FLT OPS PROC REQUIRING 1000 LBS FUEL IN THE CTR TANK IN ERROR.

Narrative: IN ACCORDANCE WITH SUPPLEMENTAL OPERATING PROC MESSAGE, CTR TANK FUEL PUMPS SECURED 1000 LBS. NO FUEL SCAVENGED OUT DURING THE NEXT 2 HRS. ARRIVED WITH ABOUT 5.6 PER MAIN TANK. ENTERED IN LOGBOOK. AFTER TALK WITH ZZZ1, DETERMINED SUPPLEMENTAL OPERATING PROC MESSAGE IN FLT PLAN STATING 1000 LBS REMAINING IS USABLE AND WILL SCAVENGE 400 LBS PER HR SAME AS B767 IS INACCURATE. MAINT CHK FOR SCAVENGE PUMP ALLOWS MINIMUM OF 200 LBS PER 1 HR 45 MINS AND THEY BELIEVE SCAVENGING ONLY STARTS LESS THAN 6000 LBS L MAIN TANK. AFTER VERIFYING SCAVENGING PUMP OP, WE CONTINUED FLT ADDING 1000 LBS TO RELEASE FUEL TO COMPLY WITH OUR PERCEIVED INTENT OF THE AIRWORTHINESS DIRECTIVE. WITH SUCH A LOW ACCEPTABLE SCAVENGE PUMP OUTPUT, I FEEL 1000 LBS REMAINING IN CTR TANK MUST BE CONSIDERED UNUSABLE BALLAST AND REFLECTED AS SUCH IN THE SUPPLEMENTAL OPERATING PROC MESSAGES AND FUEL SHEET. CAPT SHOULD NOT BE ASKED TO SIGN FLT PLAN WITH KNOWN ERRONEOUS SUPPLEMENTAL OPERATING PROC MESSAGES AND WHICH HAS INACCURATE FUEL BURN/USAGE CALCULATIONS.

Data retrieved from NASA's ASRS site as of July 2007 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.