Which factor can impede high angle fire due to overhead interference?

Overhead clearance is a critical factor in high angle fire as it refers to the amount of space available above the firing position and the projectile's flight path. When conducting high angle fire, the projectile follows a steep trajectory, which means that any overhead obstructions, such as buildings, trees, or other obstacles, can interfere with the projectile's flight path. If there is insufficient overhead clearance, the projectile can strike these obstacles before reaching its intended target, leading to a failure in delivering the intended fire support.

This concern is particularly relevant in combat situations where terrain and physical barriers can drastically alter the effectiveness of artillery and mortar systems. Therefore, ensuring adequate overhead clearance is essential to maintain effective fire support and achieve mission objectives without risking collateral damage or incurring friendly fire incidents.