Narrative:

All preflight and loading went normally. The operations agent handed in the load sheet. The first officer started his calculations on the opc and I did a review of the load sheet. The math added up and the gals added were correct. The flight attendant handed in the napkin and the passenger count matched at 98. That gave us a reduced N1 of 91.3 (approximately). Takeoff and initial climb was normal; though we both commented that the old B-300 was not impressing us with its performance. At 13000 ft; north of fmg; rno called us to revise our ZFW and takeoff weight. The revised numbers were: ZFW 102344; takeoff weight 112946 versus load sheet ZFW 96645; takeoff weight 107247. The actual passenger count was off by 30; 128 versus 98. I called the flight attendant and asked how many passenger we really had back there. She instantly knew we had 128 and that she had accidentally written 98. I recomputed the data in the opc and the revised takeoff N1 was 93.8 (approximately). We updated the FMC with the correct weight; and the remainder of the flight was uneventful. When we landed; I spoke with the a flight attendant and emphasized she is our safety net. She had counted correctly; but heard 98 and wrote it down. The operations agent did not add the through count. Should the computer not know there are some through passenger?

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Original NASA ASRS Text

Title: B737-300 FLT CREW WAS GIVEN INCORRECT WEIGHT PRIOR TO TKOF. CORRECT INFO WAS RELAYED TO CREW AFTER AIRBORNE.

Narrative: ALL PREFLT AND LOADING WENT NORMALLY. THE OPS AGENT HANDED IN THE LOAD SHEET. THE FO STARTED HIS CALCULATIONS ON THE OPC AND I DID A REVIEW OF THE LOAD SHEET. THE MATH ADDED UP AND THE GALS ADDED WERE CORRECT. THE FLT ATTENDANT HANDED IN THE NAPKIN AND THE PAX COUNT MATCHED AT 98. THAT GAVE US A REDUCED N1 OF 91.3 (APPROX). TKOF AND INITIAL CLB WAS NORMAL; THOUGH WE BOTH COMMENTED THAT THE OLD B-300 WAS NOT IMPRESSING US WITH ITS PERFORMANCE. AT 13000 FT; N OF FMG; RNO CALLED US TO REVISE OUR ZFW AND TKOF WT. THE REVISED NUMBERS WERE: ZFW 102344; TKOF WT 112946 VERSUS LOAD SHEET ZFW 96645; TKOF WT 107247. THE ACTUAL PAX COUNT WAS OFF BY 30; 128 VERSUS 98. I CALLED THE FLT ATTENDANT AND ASKED HOW MANY PAX WE REALLY HAD BACK THERE. SHE INSTANTLY KNEW WE HAD 128 AND THAT SHE HAD ACCIDENTALLY WRITTEN 98. I RECOMPUTED THE DATA IN THE OPC AND THE REVISED TKOF N1 WAS 93.8 (APPROX). WE UPDATED THE FMC WITH THE CORRECT WT; AND THE REMAINDER OF THE FLT WAS UNEVENTFUL. WHEN WE LANDED; I SPOKE WITH THE A FLT ATTENDANT AND EMPHASIZED SHE IS OUR SAFETY NET. SHE HAD COUNTED CORRECTLY; BUT HEARD 98 AND WROTE IT DOWN. THE OPS AGENT DID NOT ADD THE THROUGH COUNT. SHOULD THE COMPUTER NOT KNOW THERE ARE SOME THROUGH PAX?

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.