Linear and rectangular targets require orientation in terms of direction. The observer must send target description, length, width, and what else in the third transmission of the call for fire?

In the context of fire support coordination, once the observer has described the target, including details such as its length and width, it is essential to convey the target's elevation in order to enable effective engagement. The elevation gives the gunner information regarding the vertical position of the target relative to sea level or the level of the firing unit. This helps in ensuring that munitions are accurately placed on target, accounting for any changes in terrain and helping to prevent overshoot or undershoot.

For linear and rectangular targets, providing the correct orientation also involves understanding the target's dimensions in three-dimensional space. Elevation is crucial when engaging targets that are not at the same altitude as the firing unit, making it a critical component of the call for fire. Each element of the third transmission contributes to creating a clear picture for the artillery unit, ensuring that they can optimize their fire solutions effectively.