Narrative:

On tandy three arrival to sna, ILS runway 19R was selected in FMC. Waypoints on the arrival dropped out of box. (This is a well known problem with this software update.) waypoints were reentered one by one but sxc was omitted in error. After parol, aircraft turned direct albas. We caught the error after the controller notified us and vectored us back to sxc. Fortunately, the controller caught the mistake early, well before a serious problem with other traffic arose.

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Original NASA ASRS Text

Title: AN ACR FLC FLYING A B737-400 ON THE TANDY 3 ARR INTO SNA IMPROPERLY SETS UP THE FMC RESULTING IN A TRACK DEV AND INTERVENTION FROM ATC.

Narrative: ON TANDY THREE ARR TO SNA, ILS RWY 19R WAS SELECTED IN FMC. WAYPOINTS ON THE ARR DROPPED OUT OF BOX. (THIS IS A WELL KNOWN PROB WITH THIS SOFTWARE UPDATE.) WAYPOINTS WERE REENTERED ONE BY ONE BUT SXC WAS OMITTED IN ERROR. AFTER PAROL, ACFT TURNED DIRECT ALBAS. WE CAUGHT THE ERROR AFTER THE CTLR NOTIFIED US AND VECTORED US BACK TO SXC. FORTUNATELY, THE CTLR CAUGHT THE MISTAKE EARLY, WELL BEFORE A SERIOUS PROB WITH OTHER TFC AROSE.

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.