B727 FLT CREW DEPARTS ZZZ 4000 LBS LIGHTER THAN COMPUTED WT AND BAL.

Narrative

ON JAN/SAT/04; AT XA15 CDT OUR ACFT DEPARTED ZZZ; 4000 LBS LIGHTER THAN INDICATED ON OUR WT AND BAL SHEET. THE FLT PLAN/RELEASE INDICATED 4000 LBS LESS FUEL THAN THE WT AND BAL SHEET. THE PROB AROSE WHEN I DISCUSSED THE FUEL ON BOARD WITH THE WT AND BAL AGENT. BELIEVING THE FUEL WAS INDICATED CORRECTLY ON THE FORM; I FAILED TO RECHK THE ACTUAL FUEL ON BOARD WITH THE WT AND BAL FUEL ON BOARD. NORMAL HABIT PATTERNS INCLUDE RECHKING THE WT AND BAL. HOWEVER; AN ISSUE DISTR ME AND I DID NOT CONTINUE WHERE I HAD LEFT OFF. THE PRIMARY REASON THAT THE PROB AROSE WAS THE BREAK IN MY FLOW AND SUBSEQUENT LACK OF ATTN TO DETAIL TO RETURN MYSELF TO MY NORMAL FLOW/HABIT PATTERNS. THE PROB WAS DISCOVERED AFTER THE FLT WAS TERMINATED; THE FLT PLAN CLOSED; AND THE CREW LOG CLOSED OUT. AFTER CLOSING OUR FLT WITH THE COMPANY THE NUMBERS DID NOT MAKE SENSE. AT A LATER TIME I RECHKED THE PAPERWORK AND DISCOVERED THAT THE FLT PLAN/RELEASE AND THE FUEL RECEIPT DID NOT MATCH THE WT AND BAL. INITIALLY; I DID NOT THINK ANYTHING OF IT. I CONSIDERED OUR SIT TO BE BETTER THAN PLANNED DUE TO THE LIGHTER WT. WE DID NOT EXCEED ANY ACFT LIMITATIONS. THE PAPERWORK WAS TURNED IN UPON RETURN TO OUR OPS CTR. AS I CONSIDERED THE SIT IT OCCURRED TO ME THAT THIS WAS NOT MY DECISION TO MAKE. WE HAD VIOLATED COMPANY OPERATING POLICY AND I NEEDED TO GIVE THE INFO TO THE CAPT AND ALLOW HIM TO MAKE A DECISION BASED UPON THE FACTS. POOR JUDGEMENT LED TO A POOR DECISION THAT NEEDED TO BE CORRECTED. FACTORS AFFECTING THE QUALITY OF HUMAN PERFORMANCE WERE DISTR AND INATTENTION TO DETAIL AT THE TIME THE EVENT OCCURRED. FATIGUE WAS A FACTOR WHEN THE PROB WAS DISCOVERED AND IMPACTED MY JUDGEMENT AND DECISION MAKING ABILITY.