Carl Westin

6-7 Result study 2 139 = = Experienced Trainees In front Behind QS QS OM OM H H H H C C R R L L RI LD Control preference (DS 1) Aircraft choice (DS 2) Resolution type (DS 3) Direction (DS 4) 25.0% 75.0% 15.0% 10.0% 10.0% 10.0% 35.0% 40.0% 10.0% 10.0% 5.0% 5.0% 40.0% 40.0% 35.0% 35.0% - - 50.0% 50.0% 38.9% 19.4% 30.6% 27.8% 27.8% 11.1% 11.1% 11.1% 11.1% 11.1% 30.6% 30.6% 2.8% 2.8% 16.7% 16.7% H = Heading; C = Combined; R = Right; L = Left; I = Increase; D = Decrease F IGURE 6-11: Solution distribution for the Control problem classification in propor- tion (%) of total solutions, Study 2. opposite (75.0% versus 25.0%). For trainees, in front clearances were equally com- mon as behind clearances. Among experienced controllers, most solutions consisted of clearing OM behind QS (40.0%) or clearing QS behind OM (35.0%). Although these clearances also were common among trainees, the most frequent solution con- sisted of clearing QS in front of OM (38.9%). Figure 6-10(c) and (d) shows the proportion of consistent participants and problem-solving styles across trainees and experienced controllers, respectively. Notably all experienced controllers were found consistent according to the control problem classification. Four out of five (80.0%) consistently cleared the controlled aircraft behind the intruder. One participant consistently cleared the controlled air- craft ahead of the intruder (20.0%). Among trainees, three out of six solved the repeated conflict inconsistently (33.3%). Six out of nine (66.7%) were found con- sistent according, with equally many preferring to clear the controlled ahead as behind the intruder (33.3% respectively).