Narrative:

We departed with a weight and balance manifest that was inaccurate. All data regarding the zero fuel weight and zero fuel weight center of gravity were correct. However; it showed the #2 (center) fuel tank to have only 11000 pounds when; in fact; it had 10000 pounds more for a total of 21000 pounds. The weight and balance manifest thus indicated a takeoff gross weight that was 10000 pounds less than actual; and it showed a takeoff center of gravity that was further aft than actual. This led to the computation of incorrect takeoff speeds; takeoff stabilizer trim setting and takeoff performance capability. The actual takeoff and flight were uneventful and were completed without further incident. The error was discovered by the so while computing in-flight performance data. Therefore; all subsequent performance calculations were made using the correct weight and balance data. The direct consequences of this mistake were the operation of the aircraft on takeoff and departure at speeds approximately 4 KIAS slower than appropriate. However; the aircraft was operated during initial climb at a speed greater than that required to satisfy regulatory performance requirements. It was the SOP margin above V2 that was reduced. The slightly incorrect stabilizer trim resulted in the need for the PF (me) to apply a change to that trim during the initial climb. No aircraft limitations were exceeded and the fuel on board and its distribution met or exceeded all requirements. This event was made possible due to the presence of 10000 pounds of ballast fuel in the center tank that was required because of a very light payload; a somewhat uncommon occurrence. This situation requires the ramp agent using the weight and balance computer software to input the fuel load in a special way; which was done incorrectly. Subsequent review by the verifying agent; the so (who calculates the performance data); and myself failed to catch this error. I believe that the format of the fuel distribution printout on the weight and balance manifest can easily lead one to believe incorrectly that the fuel has been properly accounted for because of the ambiguous headings used. Upon reflection; it would seem that the only way to be sure to catch this error is by a thorough review of the takeoff fuel and takeoff gross weight values printed on the weight and balance manifest; paying special attention to compare those values with those expected during preflight planning by the dispatcher and printed on the flight plan/release. Obviously; I did not successfully do that in this case; even though at the time I believed I was thoroughly reviewing the weight and balance manifest in a manner in keeping with all company directives. This may be a case wherein I saw what I expected to see. Although we are trained to deal with ballast fuel loadings such as this; it had been several months since I had seen one. These sits get special attention during training because the fuel loading; fuel dump; fuel burn sequence; and weight and balance manifest are not normal and thus proper action in each regard requires one to stop and think clearly. Consequently; the flight crew discussed the fuel load distribution and the fuel dump and burn considerations. In this case; the fuel was loaded correctly and burned correctly; but the error in the weight and balance manifest went undetected. Unfortunately; the weight and balance software does not adequately check for obvious errors in entry to the fuel load; which on retrospect this was. Finally; a contributing factor was that this flight was running several hours late and the flight crew had been on duty longer than originally scheduled and had flown an extra leg. This flight was the last of the duty period before we were going into an unexpectedly shortened rest period. It should also be noted that the flight crew's schedule for this trip pairing involved back-side-of-the-clock flying; time zone changes and circadian rhythm disruptions.

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Original NASA ASRS Text

Title: FLT CREW OF B727-200 DISCOVER LOAD PLANNERS HAD FAILED TO INCLUDE 10K LBS OF BALLAST FUEL IN THE ACFT GROSS WT COMPUTATIONS. TKOF THUS MADE WITH INAPPROPRIATE V SPDS AND RWY COMPUTATIONS.

Narrative: WE DEPARTED WITH A WT AND BAL MANIFEST THAT WAS INACCURATE. ALL DATA REGARDING THE ZERO FUEL WT AND ZERO FUEL WT CTR OF GRAVITY WERE CORRECT. HOWEVER; IT SHOWED THE #2 (CTR) FUEL TANK TO HAVE ONLY 11000 LBS WHEN; IN FACT; IT HAD 10000 LBS MORE FOR A TOTAL OF 21000 LBS. THE WT AND BAL MANIFEST THUS INDICATED A TKOF GROSS WT THAT WAS 10000 LBS LESS THAN ACTUAL; AND IT SHOWED A TKOF CTR OF GRAVITY THAT WAS FURTHER AFT THAN ACTUAL. THIS LED TO THE COMPUTATION OF INCORRECT TKOF SPDS; TKOF STABILIZER TRIM SETTING AND TKOF PERFORMANCE CAPABILITY. THE ACTUAL TKOF AND FLT WERE UNEVENTFUL AND WERE COMPLETED WITHOUT FURTHER INCIDENT. THE ERROR WAS DISCOVERED BY THE SO WHILE COMPUTING INFLT PERFORMANCE DATA. THEREFORE; ALL SUBSEQUENT PERFORMANCE CALCULATIONS WERE MADE USING THE CORRECT WT AND BAL DATA. THE DIRECT CONSEQUENCES OF THIS MISTAKE WERE THE OP OF THE ACFT ON TKOF AND DEP AT SPDS APPROX 4 KIAS SLOWER THAN APPROPRIATE. HOWEVER; THE ACFT WAS OPERATED DURING INITIAL CLB AT A SPD GREATER THAN THAT REQUIRED TO SATISFY REGULATORY PERFORMANCE REQUIREMENTS. IT WAS THE SOP MARGIN ABOVE V2 THAT WAS REDUCED. THE SLIGHTLY INCORRECT STABILIZER TRIM RESULTED IN THE NEED FOR THE PF (ME) TO APPLY A CHANGE TO THAT TRIM DURING THE INITIAL CLB. NO ACFT LIMITATIONS WERE EXCEEDED AND THE FUEL ON BOARD AND ITS DISTRIBUTION MET OR EXCEEDED ALL REQUIREMENTS. THIS EVENT WAS MADE POSSIBLE DUE TO THE PRESENCE OF 10000 LBS OF BALLAST FUEL IN THE CTR TANK THAT WAS REQUIRED BECAUSE OF A VERY LIGHT PAYLOAD; A SOMEWHAT UNCOMMON OCCURRENCE. THIS SIT REQUIRES THE RAMP AGENT USING THE WT AND BAL COMPUTER SOFTWARE TO INPUT THE FUEL LOAD IN A SPECIAL WAY; WHICH WAS DONE INCORRECTLY. SUBSEQUENT REVIEW BY THE VERIFYING AGENT; THE SO (WHO CALCULATES THE PERFORMANCE DATA); AND MYSELF FAILED TO CATCH THIS ERROR. I BELIEVE THAT THE FORMAT OF THE FUEL DISTRIBUTION PRINTOUT ON THE WT AND BAL MANIFEST CAN EASILY LEAD ONE TO BELIEVE INCORRECTLY THAT THE FUEL HAS BEEN PROPERLY ACCOUNTED FOR BECAUSE OF THE AMBIGUOUS HDGS USED. UPON REFLECTION; IT WOULD SEEM THAT THE ONLY WAY TO BE SURE TO CATCH THIS ERROR IS BY A THOROUGH REVIEW OF THE TKOF FUEL AND TKOF GROSS WT VALUES PRINTED ON THE WT AND BAL MANIFEST; PAYING SPECIAL ATTN TO COMPARE THOSE VALUES WITH THOSE EXPECTED DURING PREFLT PLANNING BY THE DISPATCHER AND PRINTED ON THE FLT PLAN/RELEASE. OBVIOUSLY; I DID NOT SUCCESSFULLY DO THAT IN THIS CASE; EVEN THOUGH AT THE TIME I BELIEVED I WAS THOROUGHLY REVIEWING THE WT AND BAL MANIFEST IN A MANNER IN KEEPING WITH ALL COMPANY DIRECTIVES. THIS MAY BE A CASE WHEREIN I SAW WHAT I EXPECTED TO SEE. ALTHOUGH WE ARE TRAINED TO DEAL WITH BALLAST FUEL LOADINGS SUCH AS THIS; IT HAD BEEN SEVERAL MONTHS SINCE I HAD SEEN ONE. THESE SITS GET SPECIAL ATTN DURING TRAINING BECAUSE THE FUEL LOADING; FUEL DUMP; FUEL BURN SEQUENCE; AND WT AND BAL MANIFEST ARE NOT NORMAL AND THUS PROPER ACTION IN EACH REGARD REQUIRES ONE TO STOP AND THINK CLRLY. CONSEQUENTLY; THE FLT CREW DISCUSSED THE FUEL LOAD DISTRIBUTION AND THE FUEL DUMP AND BURN CONSIDERATIONS. IN THIS CASE; THE FUEL WAS LOADED CORRECTLY AND BURNED CORRECTLY; BUT THE ERROR IN THE WT AND BAL MANIFEST WENT UNDETECTED. UNFORTUNATELY; THE WT AND BAL SOFTWARE DOES NOT ADEQUATELY CHK FOR OBVIOUS ERRORS IN ENTRY TO THE FUEL LOAD; WHICH ON RETROSPECT THIS WAS. FINALLY; A CONTRIBUTING FACTOR WAS THAT THIS FLT WAS RUNNING SEVERAL HRS LATE AND THE FLT CREW HAD BEEN ON DUTY LONGER THAN ORIGINALLY SCHEDULED AND HAD FLOWN AN EXTRA LEG. THIS FLT WAS THE LAST OF THE DUTY PERIOD BEFORE WE WERE GOING INTO AN UNEXPECTEDLY SHORTENED REST PERIOD. IT SHOULD ALSO BE NOTED THAT THE FLT CREW'S SCHEDULE FOR THIS TRIP PAIRING INVOLVED BACK-SIDE-OF-THE-CLOCK FLYING; TIME ZONE CHANGES AND CIRCADIAN RHYTHM DISRUPTIONS.

Data retrieved from NASA's ASRS site as of January 2009 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.