Which correction refers to the deviation of projectile trajectory?

The term that refers to the deviation of a projectile trajectory is "Deviation." In the context of artillery and fire support operations, deviation is critical because it indicates how far a projectile may veer from its intended path due to various factors such as wind, barrel wear, and environmental conditions. Understanding deviation helps operators make the necessary adjustments to accurately hit the intended target.

The other terms do not specifically address projectile trajectory deviation. "Volume" generally refers to the amount of explosive or the number of rounds used rather than the trajectory itself. "OT Direction" denotes the direction of the target or point of interest, which is important for targeting but does not imply trajectory deviation. Finally, "Method of Fire" refers to the specific way a fire mission is executed, including aspects like the number of rounds fired and the timing of fire, but it does not concern itself directly with the deviation a projectile might exhibit during its flight.