Narrative:

Flight was released on a transcontinental flight plan west coast to east coast. Flight plan was an nrp route (computer selected based on best winds, etc). Following original release load planner sent payload increase. Dispatch re-ran flight plan with payload increase and sent amended release/flight plan with higher burn. After flight departed, an ACARS message was sent to dispatch indicating a discrepancy in the flight plan route from the first release as compared to the subsequent release. Flight had taken route on the last release/flight plan which differed from the first (which was the one that was on file with ATC). ZOA called the flight on the deviation from filed route. After reviewing the flight plans, dispatch noticed that the computer ran a different route from the original. The flight planning system is not supposed to run a different route unless specifically commanded to do so. The original route is 'hard-wired' in and is not supposed to change without positive dispatcher inputs. No such inputs were made by dispatch. The flight planning system is new (designed in-house by programmers) and is only used on 3 fleet types due to its experimental nature. The discrepancy was brought to the programmer's attention. High workload due to east coast WX and airport field conditions contributed to dispatch not noticing change in route. Also contributing was reliance on computer to do what it is supposed to do and the expectation that if no changes are made to the route then the computer will use the original route as it's designed. The new flight planning system is currently the 'default' system on the 3 fleet types.

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Original NASA ASRS Text

Title: AN ACR DISPATCHER RPTS THAT A NEW SOFTWARE PROGRAM FOR FLT PLANNING DOES NOT PERFORM AS DESIGNED ALL OF THE TIME. IT INCORRECTLY GENERATED A NEW RTE WHEN THE ONLY CHANGE DESIRED WAS TO THE WT AND BAL.

Narrative: FLT WAS RELEASED ON A TRANSCONTINENTAL FLT PLAN W COAST TO E COAST. FLT PLAN WAS AN NRP RTE (COMPUTER SELECTED BASED ON BEST WINDS, ETC). FOLLOWING ORIGINAL RELEASE LOAD PLANNER SENT PAYLOAD INCREASE. DISPATCH RE-RAN FLT PLAN WITH PAYLOAD INCREASE AND SENT AMENDED RELEASE/FLT PLAN WITH HIGHER BURN. AFTER FLT DEPARTED, AN ACARS MESSAGE WAS SENT TO DISPATCH INDICATING A DISCREPANCY IN THE FLT PLAN RTE FROM THE FIRST RELEASE AS COMPARED TO THE SUBSEQUENT RELEASE. FLT HAD TAKEN RTE ON THE LAST RELEASE/FLT PLAN WHICH DIFFERED FROM THE FIRST (WHICH WAS THE ONE THAT WAS ON FILE WITH ATC). ZOA CALLED THE FLT ON THE DEV FROM FILED RTE. AFTER REVIEWING THE FLT PLANS, DISPATCH NOTICED THAT THE COMPUTER RAN A DIFFERENT RTE FROM THE ORIGINAL. THE FLT PLANNING SYS IS NOT SUPPOSED TO RUN A DIFFERENT RTE UNLESS SPECIFICALLY COMMANDED TO DO SO. THE ORIGINAL RTE IS 'HARD-WIRED' IN AND IS NOT SUPPOSED TO CHANGE WITHOUT POSITIVE DISPATCHER INPUTS. NO SUCH INPUTS WERE MADE BY DISPATCH. THE FLT PLANNING SYS IS NEW (DESIGNED IN-HOUSE BY PROGRAMMERS) AND IS ONLY USED ON 3 FLEET TYPES DUE TO ITS EXPERIMENTAL NATURE. THE DISCREPANCY WAS BROUGHT TO THE PROGRAMMER'S ATTN. HIGH WORKLOAD DUE TO E COAST WX AND ARPT FIELD CONDITIONS CONTRIBUTED TO DISPATCH NOT NOTICING CHANGE IN RTE. ALSO CONTRIBUTING WAS RELIANCE ON COMPUTER TO DO WHAT IT IS SUPPOSED TO DO AND THE EXPECTATION THAT IF NO CHANGES ARE MADE TO THE RTE THEN THE COMPUTER WILL USE THE ORIGINAL RTE AS IT'S DESIGNED. THE NEW FLT PLANNING SYS IS CURRENTLY THE 'DEFAULT' SYS ON THE 3 FLEET TYPES.

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.