Narrative:

We received our final weight and data record via the aircraft ACARS at our departure gate and entered the data into the FMS. The selected runway was runway 26L which is the ATC preferred runway for the assigned departure. Right before pushback; an updated weight and data record was sent accounting for a 5500 pound increase in cargo. This additional weight put us where a headwind was required for a takeoff on runway 26L. We decided to ask for and got from ATC; approval for a takeoff on runway 27R which was significantly more favorable. The taxi; takeoff; climb; and initial cruise were uneventful. An hour after takeoff; we were sent a message from our dispatcher saying an additional 7500 pounds of cargo had been added that had not been accounted for on the weight and data update we received before departure and therefore; not accounted for on the takeoff performed. Shortly thereafter; we received a full final weight and data record and a new dispatch release; both reflecting the additional cargo. The new weight and data record showed us overweight for any takeoff on runway 26L but numbers for runway 27R were available. We entered the corrected data into the FMS and confirmed with our dispatcher that a load audit had been initiated. The rest of the flight was uneventful. This event was apparently caused by a breakdown in the procedures that let us know our aircraft weight and allow us to select a suitable runway and enter the proper takeoff settings. While we followed our procedures correctly; the data we based our takeoff selections on was incorrect and could have resulted in a more serious event. Had we taken off on runway 26L which according to our data we were legal to do; our actual weight; unbeknownst to us; would have had us taking off on an insufficient runway. We have submitted an operations report along with our dispatcher for review and corrective action.

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Original NASA ASRS Text

Title: WELL INTO THEIR FLT; B767-300 FLT CREW RECEIVE UNTIMELY DATALINK REVISIONS TO WEIGHT AND BALANCE INFORMATION FOR TKOF.

Narrative: WE RECEIVED OUR FINAL WT AND DATA RECORD VIA THE ACFT ACARS AT OUR DEP GATE AND ENTERED THE DATA INTO THE FMS. THE SELECTED RWY WAS RWY 26L WHICH IS THE ATC PREFERRED RWY FOR THE ASSIGNED DEP. RIGHT BEFORE PUSHBACK; AN UPDATED WT AND DATA RECORD WAS SENT ACCOUNTING FOR A 5500 LB INCREASE IN CARGO. THIS ADDITIONAL WT PUT US WHERE A HEADWIND WAS REQUIRED FOR A TKOF ON RWY 26L. WE DECIDED TO ASK FOR AND GOT FROM ATC; APPROVAL FOR A TKOF ON RWY 27R WHICH WAS SIGNIFICANTLY MORE FAVORABLE. THE TAXI; TKOF; CLB; AND INITIAL CRUISE WERE UNEVENTFUL. AN HR AFTER TKOF; WE WERE SENT A MESSAGE FROM OUR DISPATCHER SAYING AN ADDITIONAL 7500 LBS OF CARGO HAD BEEN ADDED THAT HAD NOT BEEN ACCOUNTED FOR ON THE WT AND DATA UPDATE WE RECEIVED BEFORE DEP AND THEREFORE; NOT ACCOUNTED FOR ON THE TKOF PERFORMED. SHORTLY THEREAFTER; WE RECEIVED A FULL FINAL WT AND DATA RECORD AND A NEW DISPATCH RELEASE; BOTH REFLECTING THE ADDITIONAL CARGO. THE NEW WT AND DATA RECORD SHOWED US OVERWT FOR ANY TKOF ON RWY 26L BUT NUMBERS FOR RWY 27R WERE AVAILABLE. WE ENTERED THE CORRECTED DATA INTO THE FMS AND CONFIRMED WITH OUR DISPATCHER THAT A LOAD AUDIT HAD BEEN INITIATED. THE REST OF THE FLT WAS UNEVENTFUL. THIS EVENT WAS APPARENTLY CAUSED BY A BREAKDOWN IN THE PROCS THAT LET US KNOW OUR ACFT WT AND ALLOW US TO SELECT A SUITABLE RWY AND ENTER THE PROPER TKOF SETTINGS. WHILE WE FOLLOWED OUR PROCS CORRECTLY; THE DATA WE BASED OUR TKOF SELECTIONS ON WAS INCORRECT AND COULD HAVE RESULTED IN A MORE SERIOUS EVENT. HAD WE TAKEN OFF ON RWY 26L WHICH ACCORDING TO OUR DATA WE WERE LEGAL TO DO; OUR ACTUAL WT; UNBEKNOWNST TO US; WOULD HAVE HAD US TAKING OFF ON AN INSUFFICIENT RWY. WE HAVE SUBMITTED AN OPS RPT ALONG WITH OUR DISPATCHER FOR REVIEW AND CORRECTIVE ACTION.

Data retrieved from NASA's ASRS site as of May 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.