Narrative:

I was working combined east and west radar positions in avl approach control during a moderately busy traffic session. Runway 34 was in use with visibility approachs. Small aircraft X had departed and was being vectored swbnd toward odf VOR. Air carrier X departed, was separated from an arriving aircraft and turned swbnd on a heading to keep him separated from small aircraft X. I observed that ZTL had taken the automated handoff on air carrier Y, and I switched the aircraft to the center frequency. About that time I observed air carrier Y and small aircraft X tracked to be slowly converging, about 3 mi apart. The X was level at 8000' and air carrier Y wa climbing through 8000'. I turned small aircraft X southbound to increase sep and issued traffic. Small aircraft X reported air carrier Y in sight and I instructed him to maintain visibility sep. I estimate that the aircraft had closed to about 2 mi sep. I feel a factor involved in this situation was allowing myself to have tunnel vision, concentrating on the one traffic situation, separating and sequencing the arrs, and not keeping track of all my traffic. I think I was lulled into thinking they were separated, since I had accomplished the initial departure sep, and I failed to monitor their progress to ensure continued sep. Another factor could have been the seasonalness of our traffic. Typically in winter, the traffic slows considerably. One tends to loose the edge of working busy traffic and must concentrate harder and gear up when the traffic does increase.

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Original NASA ASRS Text

Title: AN IFR ACFT CLIMBED THROUGH AN OCCUPIED ALT, RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: I WAS WORKING COMBINED E AND W RADAR POSITIONS IN AVL APCH CTL DURING A MODERATELY BUSY TFC SESSION. RWY 34 WAS IN USE WITH VIS APCHS. SMA X HAD DEPARTED AND WAS BEING VECTORED SWBND TOWARD ODF VOR. ACR X DEPARTED, WAS SEPARATED FROM AN ARRIVING ACFT AND TURNED SWBND ON A HDG TO KEEP HIM SEPARATED FROM SMA X. I OBSERVED THAT ZTL HAD TAKEN THE AUTOMATED HDOF ON ACR Y, AND I SWITCHED THE ACFT TO THE CENTER FREQ. ABOUT THAT TIME I OBSERVED ACR Y AND SMA X TRACKED TO BE SLOWLY CONVERGING, ABOUT 3 MI APART. THE X WAS LEVEL AT 8000' AND ACR Y WA CLBING THROUGH 8000'. I TURNED SMA X SBND TO INCREASE SEP AND ISSUED TFC. SMA X RPTED ACR Y IN SIGHT AND I INSTRUCTED HIM TO MAINTAIN VIS SEP. I ESTIMATE THAT THE ACFT HAD CLOSED TO ABOUT 2 MI SEP. I FEEL A FACTOR INVOLVED IN THIS SITUATION WAS ALLOWING MYSELF TO HAVE TUNNEL VISION, CONCENTRATING ON THE ONE TFC SITUATION, SEPARATING AND SEQUENCING THE ARRS, AND NOT KEEPING TRACK OF ALL MY TFC. I THINK I WAS LULLED INTO THINKING THEY WERE SEPARATED, SINCE I HAD ACCOMPLISHED THE INITIAL DEP SEP, AND I FAILED TO MONITOR THEIR PROGRESS TO ENSURE CONTINUED SEP. ANOTHER FACTOR COULD HAVE BEEN THE SEASONALNESS OF OUR TFC. TYPICALLY IN WINTER, THE TFC SLOWS CONSIDERABLY. ONE TENDS TO LOOSE THE EDGE OF WORKING BUSY TFC AND MUST CONCENTRATE HARDER AND GEAR UP WHEN THE TFC DOES INCREASE.

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.