Narrative:

I had 6 aircraft on frequency, 3 of which were foreign air carrier's. As the MD11 leveled at 12000 ft, the conflict alert activated with traffic to the southwest of him climbing nebound. The tag showed him on a center tag climbing out of 11700 ft, then switching to an 'M' tag. ('M' tag idents that an approach sector with sct airspace took the handoff.) nobody coordinated with me to allow the VFR beechjet to climb through my airspace. By the time the conflict alert activated, there was nothing I could do. Somehow the aircraft was radar idented, allowed to climb, and handed off to another sector without approval, or traffic issued. I've been a controller for 19 yrs and it was the closest near midair that I've ever seen. I don't know if the VFR beechjet had the MD11 in sight. If he did, that pilot should have been violated for operating too close to another aircraft. The pilot was 'very concerned' about the situation, but did not call the facility after landing. Due to the volume of traffic, and my desire to speak clearly and a little slower than normal probably caused me to focus only on the aircraft on my tags and not as much on the tagged and untagged aircraft on my scope. The conflict alert did not activate as promptly as I would have liked. It activated within 2 mi and 300 ft before targets merged.

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Original NASA ASRS Text

Title: SCT CTLR CONCERNED WITH NON COORD ACFT IN HIS AIRSPACE THAT CONFLICTED WITH ANOTHER IFR ACFT.

Narrative: I HAD 6 ACFT ON FREQ, 3 OF WHICH WERE FOREIGN ACR'S. AS THE MD11 LEVELED AT 12000 FT, THE CONFLICT ALERT ACTIVATED WITH TFC TO THE SW OF HIM CLBING NEBOUND. THE TAG SHOWED HIM ON A CTR TAG CLBING OUT OF 11700 FT, THEN SWITCHING TO AN 'M' TAG. ('M' TAG IDENTS THAT AN APCH SECTOR WITH SCT AIRSPACE TOOK THE HDOF.) NOBODY COORDINATED WITH ME TO ALLOW THE VFR BEECHJET TO CLB THROUGH MY AIRSPACE. BY THE TIME THE CONFLICT ALERT ACTIVATED, THERE WAS NOTHING I COULD DO. SOMEHOW THE ACFT WAS RADAR IDENTED, ALLOWED TO CLB, AND HANDED OFF TO ANOTHER SECTOR WITHOUT APPROVAL, OR TFC ISSUED. I'VE BEEN A CTLR FOR 19 YRS AND IT WAS THE CLOSEST NEAR MIDAIR THAT I'VE EVER SEEN. I DON'T KNOW IF THE VFR BEECHJET HAD THE MD11 IN SIGHT. IF HE DID, THAT PLT SHOULD HAVE BEEN VIOLATED FOR OPERATING TOO CLOSE TO ANOTHER ACFT. THE PLT WAS 'VERY CONCERNED' ABOUT THE SIT, BUT DID NOT CALL THE FACILITY AFTER LNDG. DUE TO THE VOLUME OF TFC, AND MY DESIRE TO SPEAK CLRLY AND A LITTLE SLOWER THAN NORMAL PROBABLY CAUSED ME TO FOCUS ONLY ON THE ACFT ON MY TAGS AND NOT AS MUCH ON THE TAGGED AND UNTAGGED ACFT ON MY SCOPE. THE CONFLICT ALERT DID NOT ACTIVATE AS PROMPTLY AS I WOULD HAVE LIKED. IT ACTIVATED WITHIN 2 MI AND 300 FT BEFORE TARGETS MERGED.

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.