FDC General Knowledge For Fire Control Specialist (13J) Practice Test

In precision fire missions, range accuracy is described by the probable error in range, which is a statistical estimate of how far the actual impact range could deviate from the intended range. When this dispersion grows beyond a practical limit, the observer is informed so they know the data’s reliability and can take corrective action. The threshold used is 25 meters. If the probable error in range exceeds 25 meters, the observer is told so they can re-check the range, adjust fire data, or request a fresh range fix to maintain the desired accuracy. This value is chosen because it represents a practical limit where the spread becomes significant enough to affect hit probability, prompting corrective measures without over-flagging minor fluctuations. The other values are not the standard cutoff designations for this practice, because they either would be too small to be useful or too large to provide timely guidance for precision adjustments.