At the same time with TRACON 1.5, another version appeared that simulated in particular the military precision approach phase from the same producer and with the same file and simulation syntax, under the title RAPCON . This version, remained the unique ever PC simulator for this type of approach known as well under the term GCA for Ground Control Approach. Although it starts as a normal Terminal Area Control, at the moment a flight is put on its final track, by pressing the F2 key, the aircraft was transferred to the GCA position and the screen was changed to the equivalent Precision Approach Radar one, while the rest of the traffic was actually 'frozen', meaning that you could continue control this single aircraft and after landing, you could then move over to the previous Terminal Area Control to keep on with the rest of the traffic that had stayed at the moment you moved to the GCA position. All the commands for this particular type of control were available additionally to the standard ones for TRACON. Source: Wikipedia, "Tracon II", available under the CC-BY-SA License.