*5.2.2. Angle algorithm*

Angle algorithm is the advanced version of template algorithm because it developed from the template algorithm. Similar to the template algorithm, the lower line set as the desired set clearance of the aircraft. Angle algorithm uses some of the angles, which displayed in **Figure 4b**. For clear understanding, one should know about the following terms:


When these angles combined, one will get the perspective to the object. For smaller angles,- the total angle can be approximated by Ho/R.-The margin factor tuned to the response- of the aircraft. Further development in angle algorithm carried out, but coverage range minimized [4, 8, 9].
