Statistical Evaluation of Field of View in Airborne Radiation Survey by Comparison with the Ground-based Survey

In this study, we evaluated the field of view of airborne radiation survey which is obtained around the Fukushima Daiichi Nuclear Power Plant using the unmanned helicopter by comparison with a ground-based survey in the ambient dose rate. The field of view was evaluated from the convergence tendency of the error between airborne radiation survey value and ground-based measurement value. The convergence tendency of the error between the value of airborne radiation and the value of ground-based measurement was calculated by changing the mesh size. As a result, the field of view of airborne radiation survey at 50 m and 130 m altitudes were 100 m and 150 m mesh size respectively. These evaluation results are helpful for understanding the contour map of airborne radiation surveys. In addition, it is useful for the decision of flight conditions.