6-2 
6.1  Radar Wave With The Horizon
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6 
 
Figure 6.2    Maximum radar range 
 
 
When the height of own ship’s scanner is 10 m for instance, 
(a)  A target that can be detected at the radar range of 64 nm on the radar display is required to have a height 
of 660 m or more. 
(b)  If the height of a target is 10 m, the radar range has to be approx. 15 nm.    However, the maximum 
radar range at which a target can be detected on the radar display depends upon the size of the target 
and the weather conditions, that is, the radar range may increase or decrease depending upon those 
conditions.
Height of Radar Scanner 
Detective Range 
Height of Target 
D (nm)