What is the additional step that is not required for artillery but may be required for mortars during a registration?

The additional step that is specifically associated with mortars during a registration process is adjusting the sheaf. This step is important for mortars because it ensures that the dispersion pattern of the rounds fired meets the operational requirements for the target area.

When conducting artillery registration, the focus is primarily on achieving accurate positioning of the rounds to meet the desired impact point. Artillery systems typically have a different capability in terms of range and dispersion compared to mortars, which necessitates a more precise adjustment of the sheaf. Mortars can have more variability in the spread of their fire due to their shorter range and higher angles of fire. Therefore, the adjustment of the sheaf is crucial to ensure that the rounds land within the desired proximity of the target, considering the specific characteristics of mortar fire.

In contrast, the other steps mentioned may either not apply specifically to mortars or are common to both artillery and mortars, which is why they do not fit as the additional requirement for mortars during registration. This emphasizes the importance of understanding the unique characteristics of different types of indirect fire systems when planning and executing fire missions.