Quantification for Severe Weather Avoidance Based on Precipitation Data

In this study, we analyzed the relationship between aircraft routes and precipitation data focusing on the segment where aircraft are in the process of severe weather avoidance. Currently, pilots mainly avoid severe weather using weather information from the onboard weather radar on the basis of their knowledge and experience. Consequently, avoidance routes vary, which leads to the uncertainty of flight time while improvements of trajectory prediction are required. Also, the procedures of pilots and air traffic controllers to deal with the avoidance could be one of the factors that increases their workloads. For safer and more efficient future operation, strategic planning considering weather phenomena is of importance. For this purpose, we discussed the establishment of quantitative criteria that corresponds to pilot decision-making. As a result, it was demonstrated that the avoidance distance tends to increase as the precipitation intensity increases. Also, it was indicated that aircraft even avoids the area where the echo intensity is weak in cruise phase while passing through the area in climb and descent phases. Additionally, it was clarified that there were cases where the aircraft avoided the areas where no precipitation was observed, which could be due to phenomena such as clear air turbulence. The results suggested that precipitation intensity could be one of the criteria for severe weather avoidance.