Carl Westin

100 Automation transparency effects The designed conflict consisted of two aircraft on perpendicular headings, with aircraft A (QS1338) on heading 270, and aircraft B (OM3185) on heading 360. Both aircraft were flying the same speed (260 knots), with identical speed envelopes (200- 320 knots), and were scripted to collide at the exact center of the sector (closest point of approach of 0 nmi). Separation loss occurred after 104 seconds, unless participants intervened. Additional context traffic was included to increase scenario difficulty and pre- vent early solution of the designed conflict. The position and trajectory of context aircraft were scripted so that they did not constrain any solutions of the designed conflict. Scenario repetitions were rotated (two versions) and different exit/entry point identifiers were used. In addition, repetitions were intertwined with “dummy scenarios. These measures were used to prevent scenario recognition from affecting solutions. 5-5-5 Independent variables This study was a 2x2 repeated measures design varying advisory conformance (conformal or nonconformal) with interface representation transparency (low or high). Different automation transparency levels were achieved by varying the meta- information richness provided by the SSD in two interface representations. Fig- ure 5-1 shows the two interface representations, the low condition represented by the HB SSD (Figure 5-1(d)), and the high condition represented by the TRI SSD (Figure 5-1(c)). Conformal (cfY) advisories were individually tailored to reflect a participant’s unique conflict solutions style. In contrast, nonconformal (cfN) advi- sories represented an opposite solution style, based on that of another participant. 5-5-6 Dependent measures The following dependent measures were collected: • Acceptance of an advisory (binary, accept or reject). • Agreement with an advisory (on a 1-100 scale). • Response time (from advisory onset to accept or reject button press). • Scenario difficulty (on a 1-100 scale). • Number of SSD interactions. • Type of interaction (in heading, speed, or combinations). • Separation losses (safety).