Narrative:

Shortly after reaching cruise just east of las my (captain's) nd showed 'map not available' and would remain [so] until landing. For the next 3 hours we would receive conflicting information on our level of failure modes. My FMA displayed 1fd2; AP2; and my mcdu illuminated the FM1 light along the top row indicating per the FMS2 pilot guide that FMGC1 had failed. I would have anticipated my FMA to have shown 2fd2 but it did not. A little later my FMA showed '-FD2' and then again later show 1fd2 while both FD's remained on. On the mcdu scratch pad I would occasionally show 'independent operation' or 'opp FMGC in progress'. When we were done with the weather radar we tried to select terr but were unable to select further indicating failure of FMGC1. My mcdu could operate the ACARS but not the FMGC on either side. I had to look cross cockpit to use the first officer's nd and use his mcdu to input information. On the data page FMGC1 showed blanks for lats and longs. All other indications of location were close and agreed with raw data off VOR's. We reviewed system resets and per the procedure we did not touch any circuit breakers for FMGC's since we were airborne. We did however locate all applicable circuit breakers in the event we would need to reset them later. We studied the FMGC dual failure irregular checklist and the additional procedures for standby navigation in the event FMGC2 would fail. I tested my rnp's ability to manually tune VOR's and ILS's on the nd which it did. I never did get any ILS indications on my pfd which I thought I would have at some point. Additionally; we turned off both FD's for 5 min to see if we could get FMGC1 to re-synch with no luck. We then contacted dispatch to advise and got a phone patch with maintenance control to discuss. He confirmed that we had done all that was available and with the good weather decided to continue on to destination. Things were pretty much routine until turning an 8 mile final for 27L ord. The first officer turned off the autopilot and autothrust. At the time we were in heading and vs -1200. We were set up for the ILS with the ILS 27L in the flight plan; both FD's on; ls buttons selected on with the correct data showing on the rad page. He asked for the approach mode which would not arm. I tried the localizer mode and that would not arm as well. We remained in heading and vs -1200 down final. I tried de-selecting my FD and ls and using just raw data on the nd while in the ILS mode and still could not get approach to arm. At around 700-800 ft got an ECAM for cabin attendant pr- ldg elev fault. I set the landing elev manually per the ECAM. Later at about 400 ft I got a mcdu scratch pad note indicating I had lost my speed target on my speed tape and to reference the vls indication. We were indicating about 135-140 KTS. And that sounded reasonable. The first officer later reported his speed target appeared normal. After landing normally we confirmed that the outflow valve had indeed opened properly before pulling up to the gate. Reflecting back if I were to see an FMGC failure like this in the future I would not continue on into adverse weather as we were limited to a raw data approach at the destination. In a similar scenario I think it would have benefited us to pull the circuit breaker for FMGC1 forcing a complete shutdown of FMGC1 instead of what appeared to be partial and inconsistent operation of it.

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Original NASA ASRS Text

Title: An A320 Flight Crew reported multiple and varied autoflight and FMS system anomalies which they were unable to correct. Despite this they continued to their destination. Fair weather enroute and at their destination contributed to the decision to continue.

Narrative: Shortly after reaching cruise just east of LAS my (Captain's) ND showed 'map not available' and would remain [so] until landing. For the next 3 hours we would receive conflicting information on our level of failure modes. My FMA displayed 1FD2; AP2; and my MCDU illuminated the FM1 light along the top row indicating per the FMS2 Pilot Guide that FMGC1 had failed. I would have anticipated my FMA to have shown 2FD2 but it did not. A little later my FMA showed '-FD2' and then again later show 1FD2 while both FD's remained on. On the MCDU scratch pad I would occasionally show 'independent operation' or 'opp FMGC in Progress'. When we were done with the weather radar we tried to select TERR but were unable to select further indicating failure of FMGC1. My MCDU could operate the ACARS but not the FMGC on either side. I had to look cross cockpit to use the First Officer's ND and use his MCDU to input information. On the data page FMGC1 showed blanks for lats and longs. All other indications of location were close and agreed with raw data off VOR's. We reviewed system resets and per the procedure we did not touch any circuit breakers for FMGC's since we were airborne. We did however locate all applicable circuit breakers in the event we would need to reset them later. We studied the FMGC dual failure irregular checklist and the additional procedures for standby navigation in the event FMGC2 would fail. I tested my RNP's ability to manually tune VOR's and ILS's on the ND which it did. I never did get any ILS indications on my PFD which I thought I would have at some point. Additionally; we turned off both FD's for 5 min to see if we could get FMGC1 to re-synch with no luck. We then contacted Dispatch to advise and got a phone patch with Maintenance Control to discuss. He confirmed that we had done all that was available and with the good weather decided to continue on to destination. Things were pretty much routine until turning an 8 mile final for 27L ORD. The First Officer turned off the autopilot and autothrust. At the time we were in HDG and VS -1200. We were set up for the ILS with the ILS 27L in the flight plan; both FD's on; LS buttons selected on with the correct data showing on the RAD page. He asked for the approach mode which would not arm. I tried the LOC mode and that would not arm as well. We remained in HDG and VS -1200 down final. I tried de-selecting my FD and LS and using just raw data on the ND while in the ILS mode and still could not get approach to arm. At around 700-800 FT got an ECAM for CAB PR- LDG Elev Fault. I set the landing Elev manually per the ECAM. Later at about 400 FT I got a MCDU scratch pad note indicating I had lost my speed target on my speed tape and to reference the VLS indication. We were indicating about 135-140 KTS. and that sounded reasonable. The First Officer later reported his speed target appeared normal. After landing normally we confirmed that the outflow valve had indeed opened properly before pulling up to the gate. Reflecting back if I were to see an FMGC failure like this in the future I would not continue on into adverse weather as we were limited to a raw data approach at the destination. In a similar scenario I think it would have benefited us to pull the circuit breaker for FMGC1 forcing a complete shutdown of FMGC1 instead of what appeared to be partial and inconsistent operation of it.

Data retrieved from NASA's ASRS site as of April 2012 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.