Small Aircraft; Low Wing; 1 Eng; Fixed Gear
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 4.5
Confusion; Human-Machine Interface; Workload; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance
Chart Or Publication; ATC Equipment / Nav Facility / Buildings; Procedure
There were multiple aircraft in holding patterns over OCN VORTAC. Some were VFR and some were IFR. When the data blocks would pass each other the digital targets would jump and move to the position of the other aircraft. While this was happening I took control of an IFR aircraft with the assumption that they were now VFR based off their position. I incorrectly gave an IFR aircraft an altitude restriction that would provide 500 feet with another IFR aircraft. I did so thinking the first aircraft was VFR. The two aircraft were both in holding over OCN VOR one at 2500 feet and the other aircraft at 3000 feet. There has been a lot of reports about the new STARS equipment and the jumping targets. I do not fully blame the jumping on my failure to maintain situational awareness on the sector; but I do consider it the contributing distraction that caused my break in awareness. I recommend additional work on the new STARS software to eliminate the jumping of digital targets.
SCT Controller thought an aircraft that was on an IFR flight plan was on a VFR flight plan. The controller used 500 feet vertical separation in a holding pattern instead of 1000 feet. The targets on the STARS radar display were jumping back and forth from their actual position.