Narrative:

While programming the FMC for the flight; I got a GPS-left invalid message. I checked the date of the FMC software and all the flight plan routing and everything else checked out ok. I let the captain know about the message but could not figure why we would get this message in a -300 without a GPS. When we rotated and started our climb; the FMC data for N1 settings dropped out of the FMC. We got the numbers for our climb from the performance document and continued. The FMC would not give us numbers for the calculated descent profiles. We sent an ACARS message to maintenance to meet us when we landed. Everything worked fine on the ground and maintenance said it was ok to continue and asked if the temperatures had dropped out of the FMC. We didn't know if they had; so they told us to keep an eye on it going to ZZZ. En route to ZZZ; the problem was intermittent and we noticed when the problem recurred; the temperatures were missing. Everything was working again on the way to our next city; but the captain noticed when we put the arrival runway in the FMC for xx in ZZZ the arrival fix showed up in the legs page. This fix was omitted in the chart update for xx dated last month. The captain checked the software update and saw that it said dated 8 months ago. The landing was uneventful and we met maintenance at the gate and let them know of the problems and the captain wrote up the discrepancies. The captain received a follow-up the next day from the captain the next day and said that maintenance had loaded an FMC update for a -700. Our -300 may have possibly been mistaken for a -700. Supplemental information from acn 810182: dealing with 2 problems. First with counsel from maintenance was that N1's would disappear on takeoff and then reappear during cruise then disappear on landing. At gate all was well. En route to our next city; similar problems with same results. First officer and I agreed that we can use the opc to calculate N1's if needed for cruise and weight for optimum altitude. This morning I was commuting home and it was on the same aircraft. I spoke with the crew and told them of all of the sits that we had with the aircraft the night before. Upon arrival; I spoke with the captain and he said that they are getting the same GPS message and he was calling maintenance control. The captain called this afternoon to follow up on the problem. He said that upon arriving in ZZZ1; he was met by maintenance and that they surmised that maintenance in previous city had loaded -700 FMC data into the -300 FMC.

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Original NASA ASRS Text

Title: B737-300 FLIGHT CREW FLIES THREE LEGS WITH RECURRING FMC AND N1 ANOMALIES BECAUSE A B737-700 FMC DATABASE HAD BEEN LOADED INTO THE OLDER B737-300 FMC.

Narrative: WHILE PROGRAMMING THE FMC FOR THE FLT; I GOT A GPS-L INVALID MESSAGE. I CHKED THE DATE OF THE FMC SOFTWARE AND ALL THE FLT PLAN ROUTING AND EVERYTHING ELSE CHKED OUT OK. I LET THE CAPT KNOW ABOUT THE MESSAGE BUT COULD NOT FIGURE WHY WE WOULD GET THIS MESSAGE IN A -300 WITHOUT A GPS. WHEN WE ROTATED AND STARTED OUR CLB; THE FMC DATA FOR N1 SETTINGS DROPPED OUT OF THE FMC. WE GOT THE NUMBERS FOR OUR CLB FROM THE PERFORMANCE DOCUMENT AND CONTINUED. THE FMC WOULD NOT GIVE US NUMBERS FOR THE CALCULATED DSCNT PROFILES. WE SENT AN ACARS MESSAGE TO MAINT TO MEET US WHEN WE LANDED. EVERYTHING WORKED FINE ON THE GND AND MAINT SAID IT WAS OK TO CONTINUE AND ASKED IF THE TEMPS HAD DROPPED OUT OF THE FMC. WE DIDN'T KNOW IF THEY HAD; SO THEY TOLD US TO KEEP AN EYE ON IT GOING TO ZZZ. ENRTE TO ZZZ; THE PROB WAS INTERMITTENT AND WE NOTICED WHEN THE PROB RECURRED; THE TEMPS WERE MISSING. EVERYTHING WAS WORKING AGAIN ON THE WAY TO OUR NEXT CITY; BUT THE CAPT NOTICED WHEN WE PUT THE ARR RWY IN THE FMC FOR XX IN ZZZ THE ARR FIX SHOWED UP IN THE LEGS PAGE. THIS FIX WAS OMITTED IN THE CHART UPDATE FOR XX DATED LAST MONTH. THE CAPT CHKED THE SOFTWARE UPDATE AND SAW THAT IT SAID DATED 8 MONTHS AGO. THE LNDG WAS UNEVENTFUL AND WE MET MAINT AT THE GATE AND LET THEM KNOW OF THE PROBS AND THE CAPT WROTE UP THE DISCREPANCIES. THE CAPT RECEIVED A FOLLOW-UP THE NEXT DAY FROM THE CAPT THE NEXT DAY AND SAID THAT MAINT HAD LOADED AN FMC UPDATE FOR A -700. OUR -300 MAY HAVE POSSIBLY BEEN MISTAKEN FOR A -700. SUPPLEMENTAL INFO FROM ACN 810182: DEALING WITH 2 PROBS. FIRST WITH COUNSEL FROM MAINT WAS THAT N1'S WOULD DISAPPEAR ON TKOF AND THEN REAPPEAR DURING CRUISE THEN DISAPPEAR ON LNDG. AT GATE ALL WAS WELL. ENRTE TO OUR NEXT CITY; SIMILAR PROBS WITH SAME RESULTS. FO AND I AGREED THAT WE CAN USE THE OPC TO CALCULATE N1'S IF NEEDED FOR CRUISE AND WT FOR OPTIMUM ALT. THIS MORNING I WAS COMMUTING HOME AND IT WAS ON THE SAME ACFT. I SPOKE WITH THE CREW AND TOLD THEM OF ALL OF THE SITS THAT WE HAD WITH THE ACFT THE NIGHT BEFORE. UPON ARR; I SPOKE WITH THE CAPT AND HE SAID THAT THEY ARE GETTING THE SAME GPS MESSAGE AND HE WAS CALLING MAINT CTL. THE CAPT CALLED THIS AFTERNOON TO FOLLOW UP ON THE PROB. HE SAID THAT UPON ARRIVING IN ZZZ1; HE WAS MET BY MAINT AND THAT THEY SURMISED THAT MAINT IN PREVIOUS CITY HAD LOADED -700 FMC DATA INTO THE -300 FMC.

Data retrieved from NASA's ASRS site as of May 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.