A new numerical method for calculating weather conditions has been developed for airborne radar systems for Arctic purposes. Based on the numerical method obtained in the study, software was developed that takes into account various models of electromagnetic wave propagation in various weather conditions. The results of calculations for estimating the detection range of dangerous weather conditions are presented. This assessment indicates that the threshold for detecting adverse weather conditions can be reduced. The basis for lowering the threshold without deteriorating the resulting probabilities of correct detection and false alarm is the fact that the occurrence of cases of false detection is possible only when a certain total extent of difficult weather conditions is reached, which can already be considered dangerous for the flight. The features of the formation of reflected signals from Arctic rain clouds, turbulence over a snowy desert and wind shear are considered. It is shown that all of them are characterized by lower radar reflectivity, therefore the resulting detection ranges are less than those that can be obtained at more southern latitudes, but at the same time they are sufficient for the navigation of UAVs or small aircraft.

Keywords: airborne radar, numerical methods for assessing weather conditions, weather navigation in polar latitudes, UAV navigation, hazardous weather formation

In this work, the basic relations of relativistic rocket dynamics in the case of a multicomponent jet jet are obtained and investigated. Various types of relativistic rockets with a single-component jet jet are considered as special cases of the general theory. The limiting transition to nonrelativistic rocket dynamics has been made.

Keywords: relativistic dynamics, multicomponent jet stream, ion engine, photon rocket