Narrative:

The incident occurred at the end of a midnight shift. During the shift the computer was down for about 4 hours. During this time, times were figured by the controller and some strips were hand written. The sector (OC1) was also combined with another sector (OC7). Computer came back up between XD00 local and XD30 local. During the last 3 hours of the shift (XC30-XF30), there were 26-30 aircraft in the sector with approximately 20 requests for higher altitude, as well as numerous progress reports. After the computer came back up, the flight plans for widebody transport X and widebody transport Y were re-entered into the computer. The flight plan for widebody transport X was re-entered incorrectly, showing the flight at 41 north/170 west to 41 north/160 west, when the actual route of flight was 45 north/170 west to 46N/160W. Widebody transport Y route of flight was 44N/170W to 45N/160W. The controller failed to notice the error in the route of flight, both when the strips were sequenced in the strip bays and when the flight made its progress reports when are received via teleprinter from commercial radio. Believing widebody transport X to be 3-4 degrees south of widebody transport Y, over 150 mi between routes (standard oceanic latitude sep required 100 NM), controller cleared widebody transport Y to climb to FL350, the same altitude as widebody transport X. When widebody transport X reported over 160 west, the error was discovered and widebody transport X was descended to FL330. The time the flight plans are being entered into the computer is a very busy time, for both the controllers and the air traffic assistants who are entering the flight plans. In addition, this occurs during the busiest time at oci, especially considering the aircraft are flying through a random route area where there can be, as on the night of the incident, 14 or more different routes of flight between 40 north and 46 north. In addition, it was the controller's sixth shift in a row, and had been at the sector 5 straight hours, 3 of them combined with OC7. The error could easily occur again, unless there are some restrictions placed on flts through the random route area similar to the flexible route system between hnl center and tokyo center.

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Original NASA ASRS Text

Title: ARTCC CTLR HAD LESS THAN STANDARD OCEANIC SEPARATION BETWEEN 2 WDB ACFT OVER THE PACIFIC OCEAN.

Narrative: THE INCIDENT OCCURRED AT THE END OF A MIDNIGHT SHIFT. DURING THE SHIFT THE COMPUTER WAS DOWN FOR ABOUT 4 HRS. DURING THIS TIME, TIMES WERE FIGURED BY THE CTLR AND SOME STRIPS WERE HAND WRITTEN. THE SECTOR (OC1) WAS ALSO COMBINED WITH ANOTHER SECTOR (OC7). COMPUTER CAME BACK UP BTWN XD00 LCL AND XD30 LCL. DURING THE LAST 3 HRS OF THE SHIFT (XC30-XF30), THERE WERE 26-30 ACFT IN THE SECTOR WITH APPROX 20 REQUESTS FOR HIGHER ALT, AS WELL AS NUMEROUS PROGRESS RPTS. AFTER THE COMPUTER CAME BACK UP, THE FLT PLANS FOR WDB X AND WDB Y WERE RE-ENTERED INTO THE COMPUTER. THE FLT PLAN FOR WDB X WAS RE-ENTERED INCORRECTLY, SHOWING THE FLT AT 41 N/170 W TO 41 N/160 W, WHEN THE ACTUAL ROUTE OF FLT WAS 45 N/170 W TO 46N/160W. WDB Y ROUTE OF FLT WAS 44N/170W TO 45N/160W. THE CTLR FAILED TO NOTICE THE ERROR IN THE ROUTE OF FLT, BOTH WHEN THE STRIPS WERE SEQUENCED IN THE STRIP BAYS AND WHEN THE FLT MADE ITS PROGRESS REPORTS WHEN ARE RECEIVED VIA TELEPRINTER FROM COMMERCIAL RADIO. BELIEVING WDB X TO BE 3-4 DEGS S OF WDB Y, OVER 150 MI BTWN ROUTES (STANDARD OCEANIC LAT SEP REQUIRED 100 NM), CTLR CLRED WDB Y TO CLB TO FL350, THE SAME ALT AS WDB X. WHEN WDB X RPTED OVER 160 W, THE ERROR WAS DISCOVERED AND WDB X WAS DSNDED TO FL330. THE TIME THE FLT PLANS ARE BEING ENTERED INTO THE COMPUTER IS A VERY BUSY TIME, FOR BOTH THE CTLRS AND THE AIR TFC ASSISTANTS WHO ARE ENTERING THE FLT PLANS. IN ADDITION, THIS OCCURS DURING THE BUSIEST TIME AT OCI, ESPECIALLY CONSIDERING THE ACFT ARE FLYING THROUGH A RANDOM ROUTE AREA WHERE THERE CAN BE, AS ON THE NIGHT OF THE INCIDENT, 14 OR MORE DIFFERENT ROUTES OF FLT BTWN 40 N AND 46 N. IN ADDITION, IT WAS THE CTLR'S SIXTH SHIFT IN A ROW, AND HAD BEEN AT THE SECTOR 5 STRAIGHT HOURS, 3 OF THEM COMBINED WITH OC7. THE ERROR COULD EASILY OCCUR AGAIN, UNLESS THERE ARE SOME RESTRICTIONS PLACED ON FLTS THROUGH THE RANDOM ROUTE AREA SIMILAR TO THE FLEXIBLE ROUTE SYS BTWN HNL CENTER AND TOKYO CENTER.

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