Several Enroute controllers described a loss of separation event involving a dropped Data Block.
Synopsis
Several Enroute controllers described a loss of separation event involving a dropped Data Block.
Narrative
At the time of the event I was training; we were looking for a NORDO VFR aircraft; passing an inbound to their destinations Tower; other D-Side functions; and as a trainer; I was taking notes for us to discuss later. I had prompted the trainee to point a CL30 out to the neighboring Center. After the point out was complete; the RADAR Controller climbed the CL30 to FL230 and began a hand off to the high sector. The climb placed the CL30 in a possible conflict with a PA46 level at FL190 southbound. The neighboring Center had the hand off on the PA46 and the Data Block was no longer displayed on our RADAR scope. My attention was consumed with training and looking for the NORDO VFR and I was unaware of the possible conflict. I noticed Conflict Alert activated and observed a possible conflict. I advised our Supervisor of a possible loss of separation. Reflecting back; having the sectors split would have been helpful. The complexity increased since the 40 minutes pass from the start of our shift.
Second reporter narrative
A CL30 was northbound about to level at 150. I made a point out to the neighboring Center to approve a climb. After completion of the point out; the R-Side cleared the aircraft to climb and maintain FL230. At the time I made the point out and the climb clearance was given; there was no Data Block for a PA46. The PA46 was on a southbound route at FL190 and had fallen off the scope. Upon the CL30 reaching FL190 in his climb the PA46's Data Block reappeared and the Conflict Alert went off. Recommendation; better situational awareness as to the position of all aircraft at all times.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.