Narrative:

The operations agent handed the loading schedule to the pilots. The zero fuel weight listed on the loading schedule was 83147 pounds. The takeoff weight listed on the loading schedule was 99179 pounds. Both numbers had been added correctly, and were entered into the FMC and the performance computer.. The flight departed uneventfully on time. When we called back to give ZZZ the out and off times, the radio operator told us that there was a correction to the loading schedule. We were told to make the revised zero fuel weight 84245 and the revised takeoff weight 100247 pounds, because the ramp had loaded extra bags and had not made the operations agent aware of the addition. I accomplished that task, and made the subtraction to determine the value of the actual adjustments. The subtraction yielded a net weight addition of 1098 pounds, both to the original zero fuel weight and to the original takeoff weight. I then checked the back of the loading schedule to see if this number corresponded to an actual correction. It is listed on the -300 loading schedule as the weight for 36 pieces of baggage in the aft hold. I made the corrections to the loading schedule and to the aircraft weight for the subsequent landing, and the flight arrived in ZZZ1 uneventfully ahead of schedule. Opinion/commentary: apparently, this flight departed ZZZ about 1000 pounds heavier than thought, because (apparently) the ramp did not inform operations about the additional bags that they loaded onto the aircraft. As far as I could determine, no aircraft limitations were exceeded, we did not violate the operations manual, and I do not believe that safety was compromised at all in this case. However, had we been at another location under different conditions, we could have departed unknowingly out of limits or in violation of the performance/legality required by the operations manual. The weight omission/correction in this case was just over 1% of the original takeoff weight, and did not put the aircraft close to any structural, performance or regulatory limits. However, an error of this type has definite potential to compromise safety. I am certain that both the ramp and operations know the importance of correct weight and balance numbers.

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Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED IN NON COMPLIANCE WITH THE LOADING SCHEDULE GIVEN TO THE CREW ACTUALLY 1098 LBS HEAVIER THAN SHOWN.

Narrative: THE OPS AGENT HANDED THE LOADING SCHEDULE TO THE PLTS. THE ZERO FUEL WT LISTED ON THE LOADING SCHEDULE WAS 83147 LBS. THE TKOF WT LISTED ON THE LOADING SCHEDULE WAS 99179 LBS. BOTH NUMBERS HAD BEEN ADDED CORRECTLY, AND WERE ENTERED INTO THE FMC AND THE PERFORMANCE COMPUTER.. THE FLT DEPARTED UNEVENTFULLY ON TIME. WHEN WE CALLED BACK TO GIVE ZZZ THE OUT AND OFF TIMES, THE RADIO OPERATOR TOLD US THAT THERE WAS A CORRECTION TO THE LOADING SCHEDULE. WE WERE TOLD TO MAKE THE REVISED ZERO FUEL WT 84245 AND THE REVISED TKOF WT 100247 LBS, BECAUSE THE RAMP HAD LOADED EXTRA BAGS AND HAD NOT MADE THE OPS AGENT AWARE OF THE ADDITION. I ACCOMPLISHED THAT TASK, AND MADE THE SUBTRACTION TO DETERMINE THE VALUE OF THE ACTUAL ADJUSTMENTS. THE SUBTRACTION YIELDED A NET WT ADDITION OF 1098 LBS, BOTH TO THE ORIGINAL ZERO FUEL WT AND TO THE ORIGINAL TKOF WT. I THEN CHKED THE BACK OF THE LOADING SCHEDULE TO SEE IF THIS NUMBER CORRESPONDED TO AN ACTUAL CORRECTION. IT IS LISTED ON THE -300 LOADING SCHEDULE AS THE WT FOR 36 PIECES OF BAGGAGE IN THE AFT HOLD. I MADE THE CORRECTIONS TO THE LOADING SCHEDULE AND TO THE ACFT WT FOR THE SUBSEQUENT LNDG, AND THE FLT ARRIVED IN ZZZ1 UNEVENTFULLY AHEAD OF SCHEDULE. OPINION/COMMENTARY: APPARENTLY, THIS FLT DEPARTED ZZZ ABOUT 1000 LBS HEAVIER THAN THOUGHT, BECAUSE (APPARENTLY) THE RAMP DID NOT INFORM OPS ABOUT THE ADDITIONAL BAGS THAT THEY LOADED ONTO THE ACFT. AS FAR AS I COULD DETERMINE, NO ACFT LIMITATIONS WERE EXCEEDED, WE DID NOT VIOLATE THE OPS MANUAL, AND I DO NOT BELIEVE THAT SAFETY WAS COMPROMISED AT ALL IN THIS CASE. HOWEVER, HAD WE BEEN AT ANOTHER LOCATION UNDER DIFFERENT CONDITIONS, WE COULD HAVE DEPARTED UNKNOWINGLY OUT OF LIMITS OR IN VIOLATION OF THE PERFORMANCE/LEGALITY REQUIRED BY THE OPS MANUAL. THE WT OMISSION/CORRECTION IN THIS CASE WAS JUST OVER 1% OF THE ORIGINAL TKOF WT, AND DID NOT PUT THE ACFT CLOSE TO ANY STRUCTURAL, PERFORMANCE OR REGULATORY LIMITS. HOWEVER, AN ERROR OF THIS TYPE HAS DEFINITE POTENTIAL TO COMPROMISE SAFETY. I AM CERTAIN THAT BOTH THE RAMP AND OPS KNOW THE IMPORTANCE OF CORRECT WT AND BAL NUMBERS.

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.