This study evaluates general aviation (GA) pilot performance using a mixed-modality simulated data link. Additional subjective data were gathered on workload, situation awareness (SA), and preference. Sixteen visual flight rules (VFR)-rated pilots participated in an experiment using a flight simulator equipped with a mixed-modality data link. Data link modalities were text display, synthesized speech, digitized speech, and synthesized speech/text combination. Flight conditions included VFR (unlimited ceiling and visibility) or marginal VFR flight conditions (clouds 2,800 ft above ground level, 3-mile visibility). Performance was evaluated based on the time required in accessing, understanding, and executing data link commands. Statistically significant differences were found in pilot performance, mental workload, and SA across the data link modalities. Textual data link resulted in increased time and workload as compared with the three speech-type data link conditions. SA measures indicated higher performance with textual and digitized speech data link conditions. The findings indicate that the textual data link can be significantly enhanced for single-pilot GA operations by the addition of a speech component, and that redundant presentation of data link information is preferable.
Abstract