D Directional Drilling is a method to make an inclination to a trajectory so that it can be directed onto target inside the formation which did not located vertically under the surface coordinate. Usually drilling the vertical wells much more favorable because the operation is easier and the less cost spent. So the directional drilling only applied to certain condition and special reasons. After the planning is made and directional drilling practices implemented, measured the angle and direction of boreholes. If at the points of the survey there are deviations, the directed back towards the borehole has been determined. In the implementation of directional drilling problems are more complex than conventional drilling (vertically), one of them frequent occurrence of irregularities in the surveys trajectory. Therefore, the required method of calculation of the survey result track well and accurately, one of which is the method of Minimum of Curvature and Radius of Curvature. Of the second, which is close to the result of drilling trajectory actually.