An OF fan consists of how many radial arms spaced 100 mils apart covering a total of 1,600 mils?

An OF fan is a type of fire support graphical representation used to indicate the coverage area for indirect fire systems, where the radial arms show different sectors of fire. The total spread of an OF fan is 1,600 mils, and the radial arms are spaced 100 mils apart.

To determine how many radial arms are needed, you can calculate the number of segments created by those 100 mil spacing. Since the fan covers 1,600 mils total, you would divide that by the spacing of 100 mils.

When you perform the calculation (1,600 divided by 100), you find that it produces 16 segments. However, since you also need to account for the starting point (the zero angle) at the base of the fan, you end up with 17 radial arms in total including the first arm.

This leads to the correct answer being 17, as it represents both the divisions created by the spacing and the initial reference point.