Narrative:

After departure, it was discovered that the weight and balance form had an error in the passenger weights. The company uses average passenger weights: from nov/tues to apr/sat = winter weights 170 pounds X passenger. From may/sat to oct/wed = summer weights 165 pounds X passenger. Departure schedule was set for XX59 Z. At XY01 Z, the station manager arrived at the cockpit with the load breakdown sheet. It contained the # of passenger and the totals. Due to the pressure to depart (already late) and vacate the gate (there was an air carrier X B-757 holding for it), the PNF completed the form using the computed weights provided in the load breakdown sheet. (Md-11 with 3 man crew). After takeoff, it was discovered that summer passenger weights had been used verses winter. The box on the load breakdown sheet had 165 pounds typed on the 'av weight used' box. (Form was a photocopy of the original form). The station manager that was involved was on his first departure as such. The form used was a photocopy of the prior station manager's form. It is quite possible that the prior station manager never transitioned from summer to winder weights. The error, in this case, resulted in only 290 pounds more than computed. Aircraft was well below it's maximum takeoff weight for the current conditions.

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Original NASA ASRS Text

Title: INACCURATE PAX WTS USED FOR FINAL WT AND BAL INFO.

Narrative: AFTER DEP, IT WAS DISCOVERED THAT THE WT AND BAL FORM HAD AN ERROR IN THE PAX WTS. THE COMPANY USES AVERAGE PAX WTS: FROM NOV/TUES TO APR/SAT = WINTER WTS 170 LBS X PAX. FROM MAY/SAT TO OCT/WED = SUMMER WTS 165 LBS X PAX. DEP SCHEDULE WAS SET FOR XX59 Z. AT XY01 Z, THE STATION MGR ARRIVED AT THE COCKPIT WITH THE LOAD BREAKDOWN SHEET. IT CONTAINED THE # OF PAX AND THE TOTALS. DUE TO THE PRESSURE TO DEPART (ALREADY LATE) AND VACATE THE GATE (THERE WAS AN ACR X B-757 HOLDING FOR IT), THE PNF COMPLETED THE FORM USING THE COMPUTED WTS PROVIDED IN THE LOAD BREAKDOWN SHEET. (MD-11 WITH 3 MAN CREW). AFTER TKOF, IT WAS DISCOVERED THAT SUMMER PAX WTS HAD BEEN USED VERSES WINTER. THE BOX ON THE LOAD BREAKDOWN SHEET HAD 165 LBS TYPED ON THE 'AV WT USED' BOX. (FORM WAS A PHOTOCOPY OF THE ORIGINAL FORM). THE STATION MGR THAT WAS INVOLVED WAS ON HIS FIRST DEP AS SUCH. THE FORM USED WAS A PHOTOCOPY OF THE PRIOR STATION MGR'S FORM. IT IS QUITE POSSIBLE THAT THE PRIOR STATION MGR NEVER TRANSITIONED FROM SUMMER TO WINDER WTS. THE ERROR, IN THIS CASE, RESULTED IN ONLY 290 LBS MORE THAN COMPUTED. ACFT WAS WELL BELOW IT'S MAX TKOF WT FOR THE CURRENT CONDITIONS.

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.