Narrative:

Cga X northbound A300 at FL390 requested FL410 at XB07Z. I noted he had longitudinal sep from an medium large transport (southbound A300 at FL410). They passed at XA48Z, so cga X was cleared to FL410. Mlt Y eastbound R13 at FL410. Reported coran, eagle and milks while I was working the sector. I did not realize mlt Y and cga X were traffic until mlt Y reported mils estimated catch at XB30Z. I descended mlt Y to FL390. He reported level as they passed (between XB34 and XB35Z). This is an oceanic, non radar position west/O C/a, west/O an associate controller with another set of eyes. I spotted the traffic late. I don't know why. Usually, when an aircraft requests an altitude, I know if there is someone else at it. I spotted the medium large transport, but not the mlt y--possibly because of his unusual call sign, or that he reported non compulsory reporting points (something type aircraft often do at lower altitudes, not type aircraft at FL410). Automation, visibility displays, conflict probe are essential to safety in oceanic airspace. At the time of the conflict, a pvd available to display oceanic traffic was not being employed (rsbe program). Also, the dots display was on, but was not displaying traffic and was not being monitored.

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Original NASA ASRS Text

Title: CGA CAME CLOSE TO CROSSING TRAFFIC OVER THE OCEAN IN NON RADAR ENVIRONMENT, RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: CGA X NBOUND A300 AT FL390 REQUESTED FL410 AT XB07Z. I NOTED HE HAD LONGITUDINAL SEP FROM AN MLG (SBND A300 AT FL410). THEY PASSED AT XA48Z, SO CGA X WAS CLRED TO FL410. MLT Y EBND R13 AT FL410. RPTED CORAN, EAGLE AND MILKS WHILE I WAS WORKING THE SECTOR. I DID NOT REALIZE MLT Y AND CGA X WERE TFC UNTIL MLT Y RPTED MILS ESTIMATED CATCH AT XB30Z. I DSNDED MLT Y TO FL390. HE RPTED LEVEL AS THEY PASSED (BTWN XB34 AND XB35Z). THIS IS AN OCEANIC, NON RADAR POS W/O C/A, W/O AN ASSOCIATE CTLR WITH ANOTHER SET OF EYES. I SPOTTED THE TFC LATE. I DON'T KNOW WHY. USUALLY, WHEN AN ACFT REQUESTS AN ALT, I KNOW IF THERE IS SOMEONE ELSE AT IT. I SPOTTED THE MLG, BUT NOT THE MLT Y--POSSIBLY BECAUSE OF HIS UNUSUAL CALL SIGN, OR THAT HE RPTED NON COMPULSORY RPTING POINTS (SOMETHING TYPE ACFT OFTEN DO AT LOWER ALTS, NOT TYPE ACFT AT FL410). AUTOMATION, VIS DISPLAYS, CONFLICT PROBE ARE ESSENTIAL TO SAFETY IN OCEANIC AIRSPACE. AT THE TIME OF THE CONFLICT, A PVD AVAILABLE TO DISPLAY OCEANIC TFC WAS NOT BEING EMPLOYED (RSBE PROGRAM). ALSO, THE DOTS DISPLAY WAS ON, BUT WAS NOT DISPLAYING TFC AND WAS NOT BEING MONITORED.

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.