A liquid surge effect may occur when:

The liquid surge effect occurs when the aerial apparatus's tank is not completely full due to the movement and shifting of the liquid within the tank. When the tank is partially filled, the liquid can slosh around, especially during turns, stops, or starts, creating a wave or surge effect. This movement can impact the apparatus’s stability and handling, particularly in emergency situations where precise maneuvers are necessary.

Having a tank that is not full allows a significant volume of liquid to move freely within the tank, which can lead to a dynamic shift in weight and cause potential control issues. In contrast, if the tank were empty, there would be no liquid to create a surge, and if the tank were completely full, there would be less room for the liquid to move, minimizing the potential for surge effects. Therefore, understanding the implications of a partially filled tank is crucial for safe operation of aerial fire apparatus.