Cognitive errors for radar target echo direction

Radar is a useful instrument to get target information in restricted visibility and night navigation. If there are many similar targets in a close area, navigators sometimes make errors in recognizing the radar’s target direction when they find the targets in a seascape using radar information. They sometimes indicate other targets instead of their intended target by mistake. We must prevent the errors, to reduce accidents and improve safe navigation. The purpose of this paper is to investigate why navigators make mistakes when identifying the direction between the radar’s target echo on the display and the actual vessel in the seascape. We tackle this problem in three steps: 1) we propose a navigator’s radar target cognitive model; 2) we evaluate the errors of the radar target cognition and its indication in the seascape and 3) we discuss the errors with the parallax.