Any Unknown or Unlisted Aircraft Manufacturer
Air Traffic Control Time Certified In Pos 1 (yrs) 6.0
Time Pressure; Confusion; Distraction; Situational Awareness; Workload
ATC Issue All Types; Conflict NMAC; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Flight Crew Took Evasive Action
Staffing; Airspace Structure; Human Factors
I plugged into the Assist position for about five minutes because two sectors were combined and were fairly busy. I was getting rid of old flight strips and trying to keep radar tags off each other and ensure all handoffs were being made appropriately when two aircraft began conflict alerting. The Radar Controller hadn't called traffic and when he saw that the IFR aircraft we were talking to was climbing into a VFR aircraft that was actually descending but not identified and not talking to us the IFR aircraft instead responded that he was responding to an RA. After the aircraft advised they were responding to the RA the IFR aircraft was able to get the pilot in sight; the aircraft came within 200 feet or so of each other but their targets were definitively merging. The traffic was complex but it just so happened that the VFR aircraft we weren't talking to began descent.
A Center Controller reported a NMAC; after opening a Radar Assist position at combined sectors the two aircraft began flashing conflict alert.