FM 3-25.26 MAP READING AND LAND NAVIGATION

Figure 4-18. 1:50,000 coordinating scale.d. Example of Obtaining an Eight-Digit Coordinate Using 1:50,000 Scale. To ensure the scale is correctlyaligned, place it with the zero-zero point at the lower left corner of the grid square. Keeping the horizontal lineof the scale directly on top of the east-west grid line, slide the scale to the right until the vertical line of the scaletouches the point for which the coordinates are desired (Figure 4-19). Reading right, you can see that the pointlies 530 meters to the right into the grid square, which gives a right reading of 7853. Reading up, you can seethat the point lies 320 meters up into the grid square, giving an up reading of 0032.Figure 4-19. Example of obtaining an eight-digit coordinate using 1:50,000 scale.e. Recording and Reporting Grid Coordinates. Coordinates are written as one continuous number withoutspaces, parentheses, dashes, or decimal points; they must always contain an even number of digits. Therefore,whoever is to use the written coordinates must know where to make the split between the RIGHT and UPreadings. It is a military requirement that the 100,000-meter square identification letters be included in any pointdesignation. Normally, grid coordinates are determined to the nearest 100 meters (six digits) for reporting