ZMA Controllers described a loss of separation event occurring shortly after sector positions were split; the reports listing briefing procedures and late de-combining as causal factors.
Synopsis
ZMA Controllers described a loss of separation event occurring shortly after sector positions were split; the reports listing briefing procedures and late de-combining as causal factors.
Narrative
I was working the D3 position. Aside from being very short staffed; I was approaching 2 hours on position without a break. The sector was getting busy; I asked for them to split the sector; and the supervisor told me he had paged someone back to open up Sector 4. When Sector 4 was opened; the R-Side at Sector 3 was way too busy to give a position relief briefing; so I did it as the D-Side; which is a common practice. Upon giving the traffic; the R4 Controller accepted a point out on Aircraft X who was level at 6;000 FT but landed KFPR; and would be descending into our altitude stratum shortly. Aircraft X was previously NORDO. The R3 Controller shipped Aircraft Y (5;000 FT) to Sector 4 and dropped the data block while I was off line coordinating and updating my suspense bay. Conflict Alert drew my attention back to the scope; where I saw Aircraft X descending to 4;000 FT and was then turned to a 090 [degree] heading by the R3 Controller. Recommendation: split sectors [in a] timely [manner] to prevent one sector from blowing up as quick as it did.
Second reporter narrative
I started working the R3 and R4 Sectors when it started getting busy with departures and arrivals. The determination was made to split the sectors and a controller was paged back to take R4. While the controller was coming back another controller was put in to start splitting the sectors. At the time I was busy so my D-Side gave the R4 Controller the briefing which included the board and the traffic. Aircraft X was a KFPR lander level at 6;000 FT who was originally NORDO with Orlando Approach. He finally checked on in the middle of splitting the sectors so did not acknowledge him. I was in the process of flashing and switching aircraft to R4. R4 took a point out on Aircraft X since he was a FPR lander. Aircraft Y was an overflight at 5;000 FT in R4 airspace so I flashed and shipped him on to R4. I then accidentally dropped the data block on Aircraft Y. I got back to Aircraft X and turned him 30L for traffic and to set him up for the arrival side of KFPR. Then; forgetting about Aircraft Y; since I dropped him; I descended Aircraft X for FPR. Conflict Alert went off and I turned Aircraft X to a 90 degree heading and expedited his descent. I did not call traffic. Looking back I thought I did but I did not. Don't let the D-side do the traffic briefings.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.