Slant range
In radio electronics, especially radar terminology, slant range is the line-of-sight distance along a slant direction between two points which are not at the same level relative to a specific datum.
An example of slant range is the distance to an aircraft flying at high altitude with respect to that of the radar antenna. The slant range is the hypotenuse of the triangle represented by the altitude of the aircraft and the distance between the radar antenna and the aircraft's ground track. In the absence of altitude information, for example from a height finder, the aircraft location would be plotted farther from the antenna than its actual ground track.
