COORDINATE SYSTEMS AND TRANSFORMATIONS FOR AIR NAVIGATION TASKS

Abstract

The main types of coordinate systems, used for air navigation tasks solving that are connected with aeronautical flight control and landing provisioning are examined in the article. The basic requirements for the coordinate system choice as well as the conflicts that appear while choosing are stated.
Local coordinate systems have been studied: orthogonal, cylindrical and spherical. Advantages and disadvantages of these coordinate systems, the navigation processes at which their application is rational are mentioned. Direct and backward coordinate transformations between local coordinate systems have been shown.
Essential distinctive features of global coordinate systems' appliance connected with the Earth's model figure choosing and its mathematical description problems are shown. Basic information about the global ellipsoids and its parameters is presented. The concepts of geoid, geoid wave and reference-ellipsoid have been studied. The necessity of transitioning to the global ellipsoid and global reference systems as well as the stages of such transitioning are shown. Information about the ITRS and ITRF is given. Differences in determining the objects space coordinates in these reference systems are described. Differences in ПЗ-90 and СК-2011 application areas and their prototypes WGS-84 and NAD-83 ones are specified.
The peculiarities of global geodesic and geospheric (orthodromic) coordinate systems are examined as well as their advantages and disadvantages. Direct and backward coordinate transitions for global coordinate systems and the expressions which set the connection between geocentric and topocentric coordinate systems are illustrated.