Narrative:

We were cleared to fly the pomona 6 departure; daggett transition. While loading the CDU at the gate; the captain discussed with me that the first officer he flew with the prior week had missed the 114 degree radial into pom on departure. I told him that the answer to that problem was to fly it like the RNAV departures out of las (which I have done in the past at ont). I really can't recall how I missed the 'route' and 'perf init' prompts on the takeoff page but it was during taxi out that I saw it as I was preparing for the 'before takeoff checklist' callout from the captain. It was then that I told him that the CDU indicated that I had not completed inserting all the information on the aforementioned pages; but; upon going back to the performance page; it indeed was complete. But; on the route page I noticed that there was no runway indicated on that page; nor was there any place to type it in to accomplish a runway update prior to taking the runway. We decided to stop short of the runway and do a complete quick alignment. I reloaded the CDU and upon getting to the route page and typing in the route; again; there was no prompt for me to type in any runway. And on the takeoff page; I still had the 'route' and 'perf init' prompts on the bottom of the page even though all the performance data was completed. We discussed taking off using raw data (VOR) navigation; but then the question came up about flying the RNAV arrival into las. We both agreed that we could just tell las approach that we were not able to fly any RNAV arrs upon checking in with them. Takeoff was uneventful and I flew the pomona 6 departure without deviation. During the climb out; we could not get any waypoints on the legs page to be line selected. The captain was trying to find a way to get the LNAV to engage. What he eventually did was delete the 'at or below 8000' at pom and the 'at or above 14000' at froun from the legs page. It was then that the LNAV 'came to life.' were then able to use the system and flew into las uneventfully. On our next leg out of las; we did not encounter any of these problems. Could this be an anomaly associated with the FMC update? I have flown this departure in the past using LNAV with no problems; but this was my first time flying out of ont with this recent FMC update. The answer may lie in the update. Maybe we should see if this has happened to others. Supplemental information from acn 703190: upon taxi out in ont we noticed that the FMC did not say 'preflight complete' on the takeoff page. In fact it said; 'preflight route.' after a discussion with the first officer I learned that when programming the FMC before departure the box did not ask to activate the performance page or the route page. He said that all items were entered and all spaces filled in; but he was unable to enter the runway. There were no spaces to make the runway entry and the box did not let him activate or execute the route. We performed a fast alignment and rechked the route and everything checked perfectly; but again the FMC did not allow us to activate the route. The takeoff page said 'preflight route.' we decided to take off using only VOR's for navigation and report the FMC as having failed if there were any problems. After takeoff the LNAV was unresponsive until about 8000 ft on climb out. I tried repeatedly to enter the cruise altitude in the FMC; but it wouldn't take it until I deleted the crossing restrs on the SID. After I deleted the crossing restrs and entered the cruise altitude the FMC came alive and all pages functioned normally. In hindsight; I should have included dispatch and maintenance in the problem and possibly deferred the FMC or looked into deferring it before takeoff. I think that there may be a glitch in the software that caused this problem. We had no further problems with the FMC. On arrival in las we discussed with a mechanic what might have caused this; and he had not heard of any problems and the FMC preflted without any further problems. Callback conversation with reporters revealed the following information: both pilots indicated no further anomalies were reported that they were aware of; so this is probably not a software update problem.

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Original NASA ASRS Text

Title: A B737-300 FMC HAD A DATABASE ANOMALY.

Narrative: WE WERE CLRED TO FLY THE POMONA 6 DEP; DAGGETT TRANSITION. WHILE LOADING THE CDU AT THE GATE; THE CAPT DISCUSSED WITH ME THAT THE FO HE FLEW WITH THE PRIOR WEEK HAD MISSED THE 114 DEG RADIAL INTO POM ON DEP. I TOLD HIM THAT THE ANSWER TO THAT PROB WAS TO FLY IT LIKE THE RNAV DEPS OUT OF LAS (WHICH I HAVE DONE IN THE PAST AT ONT). I REALLY CAN'T RECALL HOW I MISSED THE 'RTE' AND 'PERF INIT' PROMPTS ON THE TKOF PAGE BUT IT WAS DURING TAXI OUT THAT I SAW IT AS I WAS PREPARING FOR THE 'BEFORE TKOF CHKLIST' CALLOUT FROM THE CAPT. IT WAS THEN THAT I TOLD HIM THAT THE CDU INDICATED THAT I HAD NOT COMPLETED INSERTING ALL THE INFO ON THE AFOREMENTIONED PAGES; BUT; UPON GOING BACK TO THE PERFORMANCE PAGE; IT INDEED WAS COMPLETE. BUT; ON THE RTE PAGE I NOTICED THAT THERE WAS NO RWY INDICATED ON THAT PAGE; NOR WAS THERE ANY PLACE TO TYPE IT IN TO ACCOMPLISH A RWY UPDATE PRIOR TO TAKING THE RWY. WE DECIDED TO STOP SHORT OF THE RWY AND DO A COMPLETE QUICK ALIGNMENT. I RELOADED THE CDU AND UPON GETTING TO THE RTE PAGE AND TYPING IN THE RTE; AGAIN; THERE WAS NO PROMPT FOR ME TO TYPE IN ANY RWY. AND ON THE TKOF PAGE; I STILL HAD THE 'RTE' AND 'PERF INIT' PROMPTS ON THE BOTTOM OF THE PAGE EVEN THOUGH ALL THE PERFORMANCE DATA WAS COMPLETED. WE DISCUSSED TAKING OFF USING RAW DATA (VOR) NAV; BUT THEN THE QUESTION CAME UP ABOUT FLYING THE RNAV ARR INTO LAS. WE BOTH AGREED THAT WE COULD JUST TELL LAS APCH THAT WE WERE NOT ABLE TO FLY ANY RNAV ARRS UPON CHKING IN WITH THEM. TKOF WAS UNEVENTFUL AND I FLEW THE POMONA 6 DEP WITHOUT DEV. DURING THE CLBOUT; WE COULD NOT GET ANY WAYPOINTS ON THE LEGS PAGE TO BE LINE SELECTED. THE CAPT WAS TRYING TO FIND A WAY TO GET THE LNAV TO ENGAGE. WHAT HE EVENTUALLY DID WAS DELETE THE 'AT OR BELOW 8000' AT POM AND THE 'AT OR ABOVE 14000' AT FROUN FROM THE LEGS PAGE. IT WAS THEN THAT THE LNAV 'CAME TO LIFE.' WERE THEN ABLE TO USE THE SYS AND FLEW INTO LAS UNEVENTFULLY. ON OUR NEXT LEG OUT OF LAS; WE DID NOT ENCOUNTER ANY OF THESE PROBS. COULD THIS BE AN ANOMALY ASSOCIATED WITH THE FMC UPDATE? I HAVE FLOWN THIS DEP IN THE PAST USING LNAV WITH NO PROBS; BUT THIS WAS MY FIRST TIME FLYING OUT OF ONT WITH THIS RECENT FMC UPDATE. THE ANSWER MAY LIE IN THE UPDATE. MAYBE WE SHOULD SEE IF THIS HAS HAPPENED TO OTHERS. SUPPLEMENTAL INFO FROM ACN 703190: UPON TAXI OUT IN ONT WE NOTICED THAT THE FMC DID NOT SAY 'PREFLT COMPLETE' ON THE TKOF PAGE. IN FACT IT SAID; 'PREFLT RTE.' AFTER A DISCUSSION WITH THE FO I LEARNED THAT WHEN PROGRAMMING THE FMC BEFORE DEP THE BOX DID NOT ASK TO ACTIVATE THE PERFORMANCE PAGE OR THE RTE PAGE. HE SAID THAT ALL ITEMS WERE ENTERED AND ALL SPACES FILLED IN; BUT HE WAS UNABLE TO ENTER THE RWY. THERE WERE NO SPACES TO MAKE THE RWY ENTRY AND THE BOX DID NOT LET HIM ACTIVATE OR EXECUTE THE RTE. WE PERFORMED A FAST ALIGNMENT AND RECHKED THE RTE AND EVERYTHING CHKED PERFECTLY; BUT AGAIN THE FMC DID NOT ALLOW US TO ACTIVATE THE RTE. THE TKOF PAGE SAID 'PREFLT RTE.' WE DECIDED TO TAKE OFF USING ONLY VOR'S FOR NAV AND RPT THE FMC AS HAVING FAILED IF THERE WERE ANY PROBS. AFTER TKOF THE LNAV WAS UNRESPONSIVE UNTIL ABOUT 8000 FT ON CLBOUT. I TRIED REPEATEDLY TO ENTER THE CRUISE ALT IN THE FMC; BUT IT WOULDN'T TAKE IT UNTIL I DELETED THE XING RESTRS ON THE SID. AFTER I DELETED THE XING RESTRS AND ENTERED THE CRUISE ALT THE FMC CAME ALIVE AND ALL PAGES FUNCTIONED NORMALLY. IN HINDSIGHT; I SHOULD HAVE INCLUDED DISPATCH AND MAINT IN THE PROB AND POSSIBLY DEFERRED THE FMC OR LOOKED INTO DEFERRING IT BEFORE TKOF. I THINK THAT THERE MAY BE A GLITCH IN THE SOFTWARE THAT CAUSED THIS PROB. WE HAD NO FURTHER PROBS WITH THE FMC. ON ARR IN LAS WE DISCUSSED WITH A MECH WHAT MIGHT HAVE CAUSED THIS; AND HE HAD NOT HEARD OF ANY PROBS AND THE FMC PREFLTED WITHOUT ANY FURTHER PROBS. CALLBACK CONVERSATION WITH REPORTERS REVEALED THE FOLLOWING INFO: BOTH PILOTS INDICATED NO FURTHER ANOMALIES WERE REPORTED THAT THEY WERE AWARE OF; SO THIS IS PROBABLY NOT A SOFTWARE UPDATE PROBLEM.

Data retrieved from NASA's ASRS site as of January 2009 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.