Narrative:

We joined the fernando 5 arrival for landing at bur. Upon arrival at flw we received clearance to descend to 11000 ft. Approaching fim VOR we received further clearance to continue descent to 9000 ft, as well as several TA callouts by ATC. Conditions were VMC, no haze. At that same time, our FMS #1 failed, causing the FMS units to un-sync. PF was heads up looking for traffic, while PNF was trying to reset the #2 FMS for arrival via ILS runway 8. By that time we had received further clearance to continue our descent to 7000 ft. A few seconds later, ATC instructed us to stop descent and turn right to a heading of 140 degrees. Apparently during the process of traffic, FMS and descent, we missed by a few seconds our turn after passing fim VOR. No TCASII TA or RA were observed, but ATC had traffic opposite bound on that particular instance. PF had traffic in sight. PIC received a request to call ATC facility upon landing. ATC had been notified of our FMS problem, as well as traffic in sight VMC. The combination of automation, attention deviations due to traffic with the first FMS failing kept us off track for a brief time. We must not rely totally on FMS's doing everything for us all the time.

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Original NASA ASRS Text

Title: DEALING WITH FLT MGMNT PROBS, A LEARJET CREW BECOMES DISTR AND MISSES A TURN ON THE ARR RESULTING IN A TFC CONFLICT.

Narrative: WE JOINED THE FERNANDO 5 ARR FOR LNDG AT BUR. UPON ARR AT FLW WE RECEIVED CLRNC TO DSND TO 11000 FT. APCHING FIM VOR WE RECEIVED FURTHER CLRNC TO CONTINUE DSCNT TO 9000 FT, AS WELL AS SEVERAL TA CALLOUTS BY ATC. CONDITIONS WERE VMC, NO HAZE. AT THAT SAME TIME, OUR FMS #1 FAILED, CAUSING THE FMS UNITS TO UN-SYNC. PF WAS HEADS UP LOOKING FOR TFC, WHILE PNF WAS TRYING TO RESET THE #2 FMS FOR ARR VIA ILS RWY 8. BY THAT TIME WE HAD RECEIVED FURTHER CLRNC TO CONTINUE OUR DSCNT TO 7000 FT. A FEW SECONDS LATER, ATC INSTRUCTED US TO STOP DSCNT AND TURN R TO A HDG OF 140 DEGS. APPARENTLY DURING THE PROCESS OF TFC, FMS AND DSCNT, WE MISSED BY A FEW SECONDS OUR TURN AFTER PASSING FIM VOR. NO TCASII TA OR RA WERE OBSERVED, BUT ATC HAD TFC OPPOSITE BOUND ON THAT PARTICULAR INSTANCE. PF HAD TFC IN SIGHT. PIC RECEIVED A REQUEST TO CALL ATC FACILITY UPON LNDG. ATC HAD BEEN NOTIFIED OF OUR FMS PROB, AS WELL AS TFC IN SIGHT VMC. THE COMBINATION OF AUTOMATION, ATTN DEVS DUE TO TFC WITH THE FIRST FMS FAILING KEPT US OFF TRACK FOR A BRIEF TIME. WE MUST NOT RELY TOTALLY ON FMS'S DOING EVERYTHING FOR US ALL THE TIME.

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.