This paper proposes algorithmic and technical solutions aimed at improving the accuracy of UAV navigation parameters without altering the onboard navigation system's structure. The main focus is on introducing additional algorithms that enhance navigation parameter estimation accuracy by processing data from external sources and eliminating unreliable information. These solutions are implemented based on a weakly coupled system for integrating measurement information, ensuring modularity and flexibility in UAV configurations with various sensors and systems. An additional module performs qualitative assessments based on environmental parameters, allowing the exclusion of unreliable information sources from the navigation loop, thereby improving overall navigation accuracy.