Narrative:

On flight from rjaa to sfo, ZOA advised we were 17 NM north of course at genco after 7.7 hour flight from rjaa. On termination, confirmed #1 and #2 INS were 18 mi and 17 mi from reference point and #3 was 30 mi. Aircraft navigation was operated with #2 in triple mix (lead unit) for first 4 hours of flight when #3 was observed to be drifting 23 NM north and 4 NM west of #'south 1 and 2.

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Original NASA ASRS Text

Title: A B747 FREIGHTER IS 17 MI OFF COURSE N OF GENCO INTXN UPON BEING PICKED UP BY ZOA COASTAL RADAR AFTER A LONG TRIP FROM THE ORIENT.

Narrative: ON FLT FROM RJAA TO SFO, ZOA ADVISED WE WERE 17 NM N OF COURSE AT GENCO AFTER 7.7 HR FLT FROM RJAA. ON TERMINATION, CONFIRMED #1 AND #2 INS WERE 18 MI AND 17 MI FROM REF POINT AND #3 WAS 30 MI. ACFT NAV WAS OPERATED WITH #2 IN TRIPLE MIX (LEAD UNIT) FOR FIRST 4 HRS OF FLT WHEN #3 WAS OBSERVED TO BE DRIFTING 23 NM N AND 4 NM W OF #'S 1 AND 2.

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.