Narrative:

On 5/X/89, I was working south feeder at XX15Z. I had several aircraft proceeding to the sacramento VOR at various altitudes. 2 arrs that needed to be descended for approach to smf, 2 departures that I restr below the arrs, and another 2 overflts. I overlooked the small transport and cleared air carrier X to 11000'. At 5 mi and closing I discovered my error and issued traffic alerts to both small transport and turned to 090 degrees, and air carrier X was turned to 270 degrees. However, I used air carrier Y call sign initially and quickly restated the turn to air carrier X, who took the turn and reported the small transport in sight. Latitude sep had decreased to 2 mi upon air carrier X sighting traffic. My scan of the traffic was hampered when the data tags of air carrier Y and small transport had overlapped. It was at this time that air carrier X called in.

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Original NASA ASRS Text

Title: AN ACR WAS DESCENDED TO AN ALT OCCUPIED BY ANOTHER ACFT RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: ON 5/X/89, I WAS WORKING S FEEDER AT XX15Z. I HAD SEVERAL ACFT PROCEEDING TO THE SACRAMENTO VOR AT VARIOUS ALTS. 2 ARRS THAT NEEDED TO BE DSNDED FOR APCH TO SMF, 2 DEPS THAT I RESTR BELOW THE ARRS, AND ANOTHER 2 OVERFLTS. I OVERLOOKED THE SMT AND CLRED ACR X TO 11000'. AT 5 MI AND CLOSING I DISCOVERED MY ERROR AND ISSUED TFC ALERTS TO BOTH SMT AND TURNED TO 090 DEGS, AND ACR X WAS TURNED TO 270 DEGS. HOWEVER, I USED ACR Y CALL SIGN INITIALLY AND QUICKLY RESTATED THE TURN TO ACR X, WHO TOOK THE TURN AND RPTED THE SMT IN SIGHT. LAT SEP HAD DECREASED TO 2 MI UPON ACR X SIGHTING TFC. MY SCAN OF THE TFC WAS HAMPERED WHEN THE DATA TAGS OF ACR Y AND SMT HAD OVERLAPPED. IT WAS AT THIS TIME THAT ACR X CALLED IN.

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.