Carl Westin

C-1 Prequel briefing 205 occurring between now and 30 seconds ahead in time. In essence, the grey, amber, and red zones indicate the “no go” areas for a resolution, whereby these zones are formed by the surrounding aircraft. So any “hole” in the ring represents a “go” area, or a potential solution, to resolve a conflict. Conflicts can be resolved by either issuing a heading clearance, or by issuing a speed clearance, or a combined heading and speed clearance. Dragging the aircraft trajectory vector to a non-red or non-amber region will only change the heading of the aircraft and resolve the conflict. Notice also that by using the mouse scroll wheel the diameter of the ring will increase / decrease. The diameter of the ring indicates the speed setting of the aircraft. Notice that changing the speed also changes the location of the “no go” bands (because of the interaction between the required so- lution speed and heading). As mentioned before, you may solve a given conflict by either or both heading and speed, as you wish. RA4743 350 250 AKON F IGURE C-4: The SSD ring showing that the aircraft is heading toward its Exit Point, but also that it is in a conflict and that a loss of separation will occur between 30 - 60 seconds ahead in time. C-1-5 Performance score In the upper left corner of the screen (Figure C-1) you will see your instantaneous performance score for the current session. This performance score indicates how ac- curately you are currently vectoring aircraft toward their respective exit points, and also how well you are doing at avoiding and resolving conflicts. The performance score is based on the average track angle errors of each aircraft (inside the sector) from their intended Exit Point. Further, each time a conflict occurs, a penalty (of 10%) is subtracted from the score for each involved aircraft (so 3 aircraft in conflict is worse (-30%) than just 2 aircraft (-20%) in conflict). Any speed change from the initial speed will affect the performance score. The larger deviation, the larger the penalty. The speed change penalty is permanent in that once a change is made it has a resulting effect on the performance score.