Narrative:

I was working the tustin radar sector without a handoff controller. Aircraft #2 (PA28) was being vectored to the ILS approach to lgb. It was north of aheim intersection heading 180 degrees at 4000 ft. Aircraft #1 (BA32) was being vectored to the ILS approach at sna. It was south of aheim descending to 4000 ft heading 360 degrees. The 2 aircraft were approximately head on and 12 mi apart (this is a common practice for this sector). I had a C172 northeast of aheim on V8 en route to pdz at 5000 ft and below it at 3000 ft a baron being vectored to the ILS at sna. The data blocks of these 2 aircraft were merged and hard to read. I changed the C172 to riverside sector frequency but I used the baron's north number. When I tried to clear the baron for the approach, I got no answer. After several calls, I realized the possible mistake and called riverside to see if the baron was on their frequency. He was. I told them to have the aircraft turn right heading 270 degrees immediately to avoid high terrain. Acfts #1 and #2 were getting close and I gave #2 a right turn and #1 a right turn to keep them apart. My action took place about the same time the conflict alert sounded. After my corrective action, I returned my attention to the baron. Aircraft #1 and #2 came within 1.2 mi of each other at 4000 ft. We have a practice of not using flight progress strips. Having them could have avoided the confusion.

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Original NASA ASRS Text

Title: CTLR WORKING BUSY SECTOR WITHOUT HELP AND WITHOUT FLT PROGRESS STRIPS HAD ACFT LOSE SEPARATION DUE TO CHANGING ANOTHER ACFT TO A WRONG FREQ AND LOSING HIS VIGILANCE WITH THE BA31 AND PA28 WHO WERE HEAD ON TFC AT THE SAME ALT. CONFLICT ALERT ACTIVATED AND CTLR WAS ABLE TO TAKE ACTION TO KEEP THE ACFT APART, BUT NOT WITH LEGAL SEPARATION.

Narrative: I WAS WORKING THE TUSTIN RADAR SECTOR WITHOUT A HDOF CTLR. ACFT #2 (PA28) WAS BEING VECTORED TO THE ILS APCH TO LGB. IT WAS N OF AHEIM INTXN HDG 180 DEGS AT 4000 FT. ACFT #1 (BA32) WAS BEING VECTORED TO THE ILS APCH AT SNA. IT WAS S OF AHEIM DSNDING TO 4000 FT HDG 360 DEGS. THE 2 ACFT WERE APPROX HEAD ON AND 12 MI APART (THIS IS A COMMON PRACTICE FOR THIS SECTOR). I HAD A C172 NE OF AHEIM ON V8 ENRTE TO PDZ AT 5000 FT AND BELOW IT AT 3000 FT A BARON BEING VECTORED TO THE ILS AT SNA. THE DATA BLOCKS OF THESE 2 ACFT WERE MERGED AND HARD TO READ. I CHANGED THE C172 TO RIVERSIDE SECTOR FREQ BUT I USED THE BARON'S N NUMBER. WHEN I TRIED TO CLR THE BARON FOR THE APCH, I GOT NO ANSWER. AFTER SEVERAL CALLS, I REALIZED THE POSSIBLE MISTAKE AND CALLED RIVERSIDE TO SEE IF THE BARON WAS ON THEIR FREQ. HE WAS. I TOLD THEM TO HAVE THE ACFT TURN R HDG 270 DEGS IMMEDIATELY TO AVOID HIGH TERRAIN. ACFTS #1 AND #2 WERE GETTING CLOSE AND I GAVE #2 A R TURN AND #1 A R TURN TO KEEP THEM APART. MY ACTION TOOK PLACE ABOUT THE SAME TIME THE CONFLICT ALERT SOUNDED. AFTER MY CORRECTIVE ACTION, I RETURNED MY ATTN TO THE BARON. ACFT #1 AND #2 CAME WITHIN 1.2 MI OF EACH OTHER AT 4000 FT. WE HAVE A PRACTICE OF NOT USING FLT PROGRESS STRIPS. HAVING THEM COULD HAVE AVOIDED THE CONFUSION.

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.