Aerospace Instrument-Making Annotation << Back The onboard radar system of casual collision prevention of the flying device with a mountain obstacle in complicated condi-tions of flight. B.M. Klimashov The new patented method of aircraft’s (airplane’s and helicopter’s) flight safety in the complicated conditions of lofty moun-tains ensuring is described. Automatical prevention of collision is ensured by the analysis of distances and approach speed of aircrafts to different mountain surfaces.