V.Y. Savostyanov - Ph.D. (Eng.), associate professor, head of laboratory in the JSC «Corporation «Phasotron-NIIR». E-mail: v-savostyanov@yandex.ru
M.P. Titov - Ph.D. (Eng.), Senior Research Scientist, JSC «Aerocon». E-mail: titovmp@mail.ru

The important factor in the decision of a problem of safety of flights is creation in the onboard radar system of a special mode of the warning of collision with the terrain obstacles, capable to provide the pilot the operative information on height of a relief at the rate of flight. At manual piloting by primary goal of a radar in this mode is a display to the indicator screen of images of a relief with which help the pilot can define degree of danger of an obstacle is and then carry out maneuver on its flight or detour. The concept of construction of such mode consists in the organization of processing of the radar information in an airborne computer in the form of three streams - controls, primary and secondary processing where primary (detection and calculation of coordinates of objects) and secondary (formation of images) processing function asynchronously, but under control of algorithms of control. A kernel of this structure is the radar map of a relief - a database about heights of elements of a relief on which basis formation of demanded images (relief sections) according to spatial moving of the vehicle and a vector of its travelling speed is under construction. Thus the pilot has possibility operatively to select a type of the image convenient for it - vertical, horizontal or planned sections of a relief. Demanded split-hair accuracy of calculation of height of the found out objects is provided with application of monopulse methods of direction finding in a vertical plane, and also an optimum filtration (by criterion of a minimum of an average square of an error) results of estimation on set of observations. Implementation of principles of functioning of such mode has been carried successfully out in JSC «Corporation «Phasotron-NIIR» both in a number of research and development works, and in the form of independent modes as a part of the software onboard radars, developed and made for various planes, helicopters or unmanned aerial vehicles.