SUBCOURSE EDITION - Modern Prepper

(3) The equivalent UTM grid values are also shown in this section of the form by thesymbols E (easting) and N (northing). The UTM grid values are computed by a topographic surveyorfrom the geographic values. The easting and northing grid values are computed to .1 meter (grounddistance) to provide the required accuracy when the projection is plotted on the grid.(4) Examine figure 3-2 again and you can determine that the UTM grid values for thenorthwest projection corner are 282740.3E and 4291794.9N. Refer back to figure 3-1 and determineUTM grid values for the remaining three corners. Compare your answers with the ones below:Southwest 281984.1E, 4264048.6NSoutheast 303788.4E, 4263485.6NNortheast 304468.8E, 4291230.8N(5) In the next section you will examine how these UTM grid values are used to plot aprojection on a grid.b. The projection corner measurements are the values that are used to plot the projectioncorners on a UTM grid. They are computed by a topographic surveyor from the UTM grid values.Figure 3-3 shows the NW projection corner obtained from DA Form 1941. Figure 3-4 shows aninterpretation of how the dimension arrows relate to this particular projection corner. In order to plotthis or any projection corner, you always plot the distance shown by the dimension arrows on DA Form1941 from the two grid lines shown for each projection corner. As shown above, point A is the locationof the projection corner to be plotted on the grid which you have previously constructed. By comparingfigure 3-3 to figure 3-4 it is seen that point A is plotted by measuring the two distances indicated by thedimension arrows shown. Essentially, point A is plotted .519 centimeters west of grid line 283 and 1.590centimeters north of grid line 4291. These measurements must be plotted from the grid lines 2b3 and4291 that are shown for this projection corner. The procedures for plotting this NW projection cornerare outlined in the next lesson. Examine figure 3-1 and determine the plotting measurements of theremaining three corners. Compare your answers with the ones in figures 3-4a, 3-4b and 3-4c.46