Effects of Levels of Automation on Air Traffic Controller Situation Awareness and Performance

To meet the increasing demands of air traffic, the Joint Planning and Development Office has proposed initiatives to modernize the U.S. National Airspace System (NAS). That proposal involves introduction of automated systems that would help air traffic controllers handle the increasing volume of traffic in their airspace (JPDO, 2007). However, a potential consequence of fully automated systems is the out-of-the-loop performance (OOP) problem (e.g., Billings, 1991; Endsley & Kiris, 1995). This refers to the reduced ability of operators working with fully automated systems to perform tasks manually following automation failure compared to operators who perform the tasks manually. The central factor that is considered responsible for the OOP problem is a loss of operator situation awareness (SA). One approach to reduce the OOP problem is to use varying levels of automation (LOA; e.g., Parasuraman, Sheridan, & Wickens, 2000). An experiment was conducted to examine the differences in the SA and collision detection performance of individuals when they worked with different levels of a collision detection system to control air traffic. Seventy-two participants controlled air traffic using one of the LOAs: information acquisition, information analysis, decision and action selection or action implementation automation (Parasuraman et al., 2000). SA was assessed by examining the extent to which individuals monitored various aircraft attributes. The time taken to detect upcoming aircraft collisions was also recorded. When the automation was unreliable, the time taken to detect aircraft collision in the higher LOAs was significantly longer compared with the information acquisition automation. This poor performance following automation failure for higher LOAs was mediated by SA for altitude and destination, with lower SA yielding poor performance. Thus, the costs associated with automation failure are greater when automation is applied to higher order stages of information processing. SA is an important cognitive issue that needs to be considered in air traffic control automation design. Results from this experiment have practical implications for automation, SA training programs, and air traffic control display design for the future NAS.