Narrative:

Cga and air carrier X were both cleared via diw with the faster air carrier X behind. When I accepted the handoffs, orf H (transferring controller) advised me that air carrier X was faster. I looked at the strip for air carrier X and read panal AR3 and told orf H that I would take care of it. To do so, I cleared cga via ilm AR1, thinking that air carrier X was cleared via J174 diw AR7, which would keep aircraft separated. When cga still seemed to be converging with air carrier X, I issued cga a 15 degree right turn. When he was sufficiently clear of J174 (air carrier X route) I reclred cga via ilm AR1. At this point I was absolutely certain the aircraft were separated. I then became involved in a situation at the northern end of the sector when air carrier X made the turn for J174 at diw. When I saw the situation I immediately turned air carrier X to a 170 degree heading and cga to a 240 degree heading. When the aircraft were separated, I reclred them back on course. This incident occurred with 15 aircraft in the sector. The cause is painfully obvious--I failed to realize the air carrier X was cleared via J174 ilm AR1 climb AR3 panal AR3. Had I realized this, or had this been brought to my attention by the d-side, I would have cleared air carrier X via J174 diw AR7 panal--a solution used daily with this type of confliction.

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Original NASA ASRS Text

Title: FASTER ACR OVERTOOK SLOWER CGA RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: CGA AND ACR X WERE BOTH CLRED VIA DIW WITH THE FASTER ACR X BEHIND. WHEN I ACCEPTED THE HDOFS, ORF H (TRANSFERRING CTLR) ADVISED ME THAT ACR X WAS FASTER. I LOOKED AT THE STRIP FOR ACR X AND READ PANAL AR3 AND TOLD ORF H THAT I WOULD TAKE CARE OF IT. TO DO SO, I CLRED CGA VIA ILM AR1, THINKING THAT ACR X WAS CLRED VIA J174 DIW AR7, WHICH WOULD KEEP ACFT SEPARATED. WHEN CGA STILL SEEMED TO BE CONVERGING WITH ACR X, I ISSUED CGA A 15 DEG RIGHT TURN. WHEN HE WAS SUFFICIENTLY CLR OF J174 (ACR X ROUTE) I RECLRED CGA VIA ILM AR1. AT THIS POINT I WAS ABSOLUTELY CERTAIN THE ACFT WERE SEPARATED. I THEN BECAME INVOLVED IN A SITUATION AT THE NORTHERN END OF THE SECTOR WHEN ACR X MADE THE TURN FOR J174 AT DIW. WHEN I SAW THE SITUATION I IMMEDIATELY TURNED ACR X TO A 170 DEG HDG AND CGA TO A 240 DEG HDG. WHEN THE ACFT WERE SEPARATED, I RECLRED THEM BACK ON COURSE. THIS INCIDENT OCCURRED WITH 15 ACFT IN THE SECTOR. THE CAUSE IS PAINFULLY OBVIOUS--I FAILED TO REALIZE THE ACR X WAS CLRED VIA J174 ILM AR1 CLB AR3 PANAL AR3. HAD I REALIZED THIS, OR HAD THIS BEEN BROUGHT TO MY ATTN BY THE D-SIDE, I WOULD HAVE CLRED ACR X VIA J174 DIW AR7 PANAL--A SOLUTION USED DAILY WITH THIS TYPE OF CONFLICTION.

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.