A B737-300 PERFORMANCE COMPUTER DID NOT ACCEPT INPUTS. THE FLT DEPARTED USING OLD DATA WHICH THEY LATER DETERMINED PROHIBITED USING THAT RWY.

Narrative

WHILE ATTEMPTING TO ENTER THE LOADING SCHEDULE DATA FOR PUSHBACK; THE PERFORMANCE COMPUTER REPEATEDLY DUMPED ENTERED DATA AND AUTOMATICALLY RESET ITSELF. AFTER SEVERAL ATTEMPTS THE PERFORMANCE COMPUTER FINALLY TOOK THE DATA AND WE WERE ABLE TO COMPLETE THE BEFORE PUSH CHKLIST. DURING PUSHBACK; THE ATIS INFO CHANGED AND WE HEARD A COMPANY ACFT CALL FOR TAXI AND RECEIVE CLRNC TO THE OPPOSITE RWY. I PULLED OUT THE PERFORMANCE COMPUTER DURING TAXI AND BEGAN ENTERING THE NEW ATIS; BUT ONCE AGAIN THE PERFORMANCE COMPUTER WOULD INCORRECTLY TRANSPOSE DATA AS I TOUCHED AN ENTRY BLOCK AND WOULD RESET ITSELF. THE CAPT ALSO TRIED TO RE-ENTER THE NEW DATA BUT ALL ATTEMPTS FAILED. AS THE ATIS INFO HAD NOT CHANGED SIGNIFICANTLY; THE WINDS HAD NOT SHIFTED THAT MUCH AND WE WERE #1 FOR TKOF; WE CONCLUDED THAT THE TKOF DATA SHOULD ALSO WORK FOR THIS RWY. THE TKOF WAS UNEVENTFUL WITH GREATER THAN 3000 FT OF RWY REMAINING. ONCE ESTABLISHED AT CRUISE; THE CAPT REMEMBERED SOME OBSTRUCTION CLRNC DIFFERENCES BTWN THE 2 RWYS AND WANTED TO VERIFY THE TKOF DATA. AGAIN AFTER STRUGGLING TO ENTER DATA ON THE PERFORMANCE COMPUTER WE DISCOVERED THAT BASED ON OUR CURRENT LOAD PLANNED WERE TOO HVY; FOR OBSTACLE CLRNC; FOR THE RWY WE USED. DO NOT RUSH; TAXI TO A MARSHALLING AREA. AS INFO CHANGES; ENSURE THE INFO IS PROPERLY LOADED INTO THE PERFORMANCE COMPUTER. IF A PIECE OF EQUIP IS NOT FUNCTIONING PROPERLY; REPLACE THE EQUIP OR IN THIS CASE HAVE OPS/DISPATCH RECALCULATE THE DATA; AND REVISE TKOF WTS AS NECESSARY. DO NOT BE/FEEL PRESSURED (IE; RUNNING LATE; GND CTL; ETC) TO COMPROMISE STANDING PROCS. CREW COORD AND PERFORMANCE COMPUTER.