During an illumination mission your round burns on the ground for 13 seconds. With a rate of descent of 5 meters per second, what is your HOB correction?

In this scenario, to determine the height of burst (HOB) correction for the illumination mission, one must calculate the height from which the illumination round was supposed to burst above the ground. The rate of descent of the illumination round is given as 5 meters per second, and the round burns for 13 seconds.

To find the distance the round descended during the burn time, we multiply the rate of descent by the time spent burning:

Distance = Rate of Descent × Time

Distance = 5 meters/second × 13 seconds = 65 meters

Since the illumination round is expected to provide effective illumination, we must adjust HOB to account for this distance the round has already descended. Thus, to achieve the intended illumination effect, we would apply a correction based on the total descent distance.

When considering typical HOB adjustments in artillery, this calculation typically involves a straightforward alignment with the unit of correction. In this case, the round has descended 65 meters, which corresponds to a correction of approximately "Up 50" in the context of adjustments on the fire control system, as this adjustment is representative of moving the point of burst higher in order to achieve the desired illumination overhead.

Therefore, the correct choice reflects the necessary upward correction to