Air Traffic Control Fully Certified
Situational Awareness
ATC Issue All Types
General None Reported / Taken
ATC Equipment / Nav Facility / Buildings; Human Factors
I was working Aircraft Y; a VFR PA46 Southbound at 12;500 FT. I had given Aircraft X; A320; the descend via clearance for LGA. The aircraft crossed over each other just South of DAVYS intersection. I had never issued a traffic call; I was coordinating off landlines with controllers in my area about a flight of 2 F16 I was working; and needed a point/handoff to adjacent sectors. The Aircraft X was at 13;400 FT and keyed up that they had they traffic in sight. The Aircraft Y then said they had the traffic in sight. The Aircraft X restriction on the descend via was to cross DAVYS at or above 13;000 FT; and the confliction point was South of DAVYS. I should have still called traffic and didn't. 'Conflict alert' goes off all the time at various sectors. It is almost a second job just to divert your attention to the 'conflict alert' and determine if it's real or not. In this case; however; I do not believe 'conflict alert' went off until they were already passed each other. See if there are any improvements on the criteria for 'conflict alert'; as well as to have real time information about actual aircraft (VFR) that will be entering our space. In this regard; ERAM should help a lot. 'Conflict alert' goes off for aircraft that appear to be climbing; but aren't actually going into our airspace; and the descend via protects for the airspace. Some controllers become complacent to the fact that 'conflict alert' goes off all the time; and it is a distraction-either to analyze continuously; or the pure distraction it is and then to ignore it; even it's real.
ZDC Controller described a VFR/IFR conflict acknowledging traffic information could have been more precise; adding that the 'conflict alert' activates all too often when separation has been established.