Narrative:

Had a C172 enroute to smo maybe 4 miles east of lgb at 4;000. Lbg tower flashed a release for an A320; which I accepted. My plan was to keep the A320 at 3;000 until in front of the slow moving cessna. Lgb tower called to say the A320 was going to be a couple minutes late on his release because they were getting jammed on final. Swiss cheese hole 1: now my plan was to turn the cessna up along the boundary to get out of the way of the A320 when he departed. But; downe sector called to use the racetrack and descend an aircraft to 5;000 (swiss cheese hole 2). This tied my hands a little on running the cessna tight to the line. Now my plan was to turn the A320 out to a 250 heading to get divergence from the cessna. However; when I turned the A320 out there was a VFR aircraft opposite direction at 2;500; which I assumed was descending for lgb; swiss cheese hole 3; but upon rechecking the situation; I noticed the VFR at 2;800. I turned the A320 to a 270 heading and he got an RA from the VFR aircraft. I then climbed the A320 to 6;000 as per the handoff. I think there should be a bit of a redesign on the bravo airspace; or a class charlie airspace to cover lgb for this departure as well as the lgb...vtu departure. On my side; once I notice the situation I should have cancelled the release with lgb; or told downe approved with the racetrack and shown my traffic (C172) and requested a point out at 4;000. Also never assume what a VFR aircraft is going to do.

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Original NASA ASRS Text

Title: SCT Controller described a conflict event when an IFR release from LGB was delayed and plans to handle a VFR aircraft failed to materialize. The reporter suggested airspace changes that might prevent future occurrences.

Narrative: Had a C172 enroute to SMO maybe 4 miles east of LGB at 4;000. LBG Tower flashed a release for an A320; which I accepted. My plan was to keep the A320 at 3;000 until in front of the slow moving Cessna. LGB Tower called to say the A320 was going to be a couple minutes late on his release because they were getting jammed on final. Swiss cheese hole 1: Now my plan was to turn the Cessna up along the boundary to get out of the way of the A320 when he departed. But; DOWNE Sector called to use the racetrack and descend an aircraft to 5;000 (swiss cheese hole 2). This tied my hands a little on running the Cessna tight to the line. Now my plan was to turn the A320 out to a 250 heading to get divergence from the Cessna. However; when I turned the A320 out there was a VFR aircraft opposite direction at 2;500; which I assumed was descending for LGB; swiss cheese hole 3; but upon rechecking the situation; I noticed the VFR at 2;800. I turned the A320 to a 270 heading and he got an RA from the VFR aircraft. I then climbed the A320 to 6;000 as per the handoff. I think there should be a bit of a redesign on the Bravo Airspace; or a Class Charlie Airspace to cover LGB for this departure as well as the LGB...VTU departure. On my side; once I notice the situation I should have cancelled the release with LGB; or told DOWNE approved with the racetrack and shown my traffic (C172) and requested a point out at 4;000. Also never assume what a VFR aircraft is going to do.

Data retrieved from NASA's ASRS site as of July 2013 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.