Narrative:

The flight was automatic-filed with ATC approximately 2 1/2 hours prior to departure from sfo. 30 mins prior to departure the captain called requesting a fuel reduction. I was involved in a diversion from bur due to WX and planning a fuel stop for a san/pit flight. I pulled the flight plan up on the computer and recalculated it with less holding fuel. I discussed the fuel with the captain and it was satisfactory. I sent the flight plan to sfo operations. After departure from sfo I received a call from sfo operations. ZOA had called to advise us that there was a problem with the flight plan routing on the flight. The flight started a turn to intercept J198 over MVA. ATC called the pilot and requested, why he was deviating from the flight plan. ATC had him filed J84-ekr-J116 etc. The captain advised them his flight plan showed J84-MVA-J198 etc. ATC rerouted him with no further incident. During the calculation of the second flight plan the computer picked up a different route number. The air carrier flight plan system is keyed to the winds aloft for route selection. Both flight plans were done within the forecast period of xa-xb. Due to a computer problem, the winds were delayed till xa. The theory is that within the 2 1/2 hours between the original flight plan and the amended flight plan, that the computer jumped forecast periods of the winds aloft. Two possible solutions are possible. To request the flight plan a second time with the original request and input a route restr in case an amended flight plan is recalculated. The second could be to have ATC issue a full clearance readback on random filed routes.

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Original NASA ASRS Text

Title: ACR PIC DEVIATES FROM ATC FILED ROUTE. TEXT INDICATES LESS THAN 30 MINUTES BEFORE DEP THE FLT PLAN WAS CHANGED WITHIN THE COMPANY. DOES NOT SPECIFY IF FILED WITH ATC. IF SO, WAS TOO LATE TO GET INTO SYSTEM.

Narrative: THE FLT WAS AUTO-FILED WITH ATC APPROX 2 1/2 HRS PRIOR TO DEP FROM SFO. 30 MINS PRIOR TO DEP THE CAPT CALLED REQUESTING A FUEL REDUCTION. I WAS INVOLVED IN A DIVERSION FROM BUR DUE TO WX AND PLANNING A FUEL STOP FOR A SAN/PIT FLT. I PULLED THE FLT PLAN UP ON THE COMPUTER AND RECALCULATED IT WITH LESS HOLDING FUEL. I DISCUSSED THE FUEL WITH THE CAPT AND IT WAS SATISFACTORY. I SENT THE FLT PLAN TO SFO OPERATIONS. AFTER DEP FROM SFO I RECEIVED A CALL FROM SFO OPERATIONS. ZOA HAD CALLED TO ADVISE US THAT THERE WAS A PROBLEM WITH THE FLT PLAN ROUTING ON THE FLT. THE FLT STARTED A TURN TO INTERCEPT J198 OVER MVA. ATC CALLED THE PLT AND REQUESTED, WHY HE WAS DEVIATING FROM THE FLT PLAN. ATC HAD HIM FILED J84-EKR-J116 ETC. THE CAPT ADVISED THEM HIS FLT PLAN SHOWED J84-MVA-J198 ETC. ATC REROUTED HIM WITH NO FURTHER INCIDENT. DURING THE CALCULATION OF THE SECOND FLT PLAN THE COMPUTER PICKED UP A DIFFERENT ROUTE NUMBER. THE ACR FLT PLAN SYSTEM IS KEYED TO THE WINDS ALOFT FOR ROUTE SELECTION. BOTH FLT PLANS WERE DONE WITHIN THE FORECAST PERIOD OF XA-XB. DUE TO A COMPUTER PROBLEM, THE WINDS WERE DELAYED TILL XA. THE THEORY IS THAT WITHIN THE 2 1/2 HRS BETWEEN THE ORIGINAL FLT PLAN AND THE AMENDED FLT PLAN, THAT THE COMPUTER JUMPED FORECAST PERIODS OF THE WINDS ALOFT. TWO POSSIBLE SOLUTIONS ARE POSSIBLE. TO REQUEST THE FLT PLAN A SECOND TIME WITH THE ORIGINAL REQUEST AND INPUT A ROUTE RESTR IN CASE AN AMENDED FLT PLAN IS RECALCULATED. THE SECOND COULD BE TO HAVE ATC ISSUE A FULL CLRNC READBACK ON RANDOM FILED ROUTES.

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.