THE VNAV TUTOR - ADDRESSING A MODE AWARENESS DIFFICULTY FOR PILOTS OFGLASS COCKPIT AIRCRAFT

One of the major tasks of pilots of modern aircraft is monitoring and understanding the status and behavior of the auto flight system, i.e., mode awareness. Central modes of the system change due to pilot comma nds (manually) or in response to system events (automatically). The fl exible and dynamic nature of the system increases both the functionali ty of the control system and the cognitive demands placed on pilots, I n order to maintain mode awareness in this dynamic environment, pilots must be continuously vigilant of indications from several locations w ithin the cockpit, Lacking accurate and complete system knowledge and interfaces that clearly present the system state and constraints, pilo ts may misunderstand the control modes, Pilots often cite vertical pat h navigation (VNAV) as a flight management system function that ''surp rises'' them, The VNAV Tutor, a computer-based training system, was de veloped to address this issue, The VNAV Tutor attempts to improve pilo ts' understanding of VNAV control modes and the interaction of the mod e control panel functions with the flight management system during VNA V usage. Furthermore, it attempts to help pilots build a robust concep tual model of vertical navigation operation, An evaluation showed that the VNAV Tutor enhanced both the conceptual understanding and the ope rational use of the vertical navigation function by pilots transitioni ng to aircraft with sophisticated auto flight systems.