The effects of automation and task difficulty on crew coordination, workload, and performance

The purposes of this research were two-fold: (1) to assess the reliability and utility of the Aircrew Coordination Observation and Evaluation scales in describing crew coordination behaviors exhibited during flight and (2) to investigate the effects of automation on crew coordination, workload, and performance. Two levels of automation (i.e., presence or absence of an autopilot) and two levels of task difficulty (i.e., presence or absence of wind and turbulence) were combined to yield a 2 x 2 design. Twenty-four two-person crews performed in both levels of automation and one of two levels of task difficulty. The results of the reliability assessment demonstrated that the training procedures and behavioral summary scale anchors that were developed produced adequate levels of interrater reliability in this investigation. The results of the crew coordination analyses revealed differences in the frequency and quality of crew coordination behaviors between levels of automation. Ratings of crew coordination were also shown to be related to performance. The results also indicated that although crews in the automated condition reported less workload, only one of the three measures of flight performance was improved. In addition, under high task difficulty, problem solving performance was worse in the automated condition than in the manual condition. Interpretation and suggestions for future research are discussed.