Which combination of factors would yield the strongest vortex from an aircraft?

The strongest vortex from an aircraft is produced by a combination of weight, speed, and the aircraft's configuration. A heavy, clean, and slow aircraft creates the most substantial wake turbulence.

When an aircraft is heavy, it generates more lift, resulting in stronger vortices as the airflow around the wings is more intense due to the greater amount of lift being produced. Clean aircraft refers to the absence of dirt or ice on the wings, which allows for smoother airflow. A slow speed is particularly significant because slower aircraft generate larger vortex sizes. When an aircraft flies at lower speeds, the air pressure differences over and under the wings increase, causing the vortices to be larger and more prominent, intensifying the wake turbulence.

This combination produces vortices that can persist longer and travel further, impacting following aircraft significantly. In contrast, lighter or faster aircraft configurations would create weaker vortices due to lower lift generation and faster movement that disperses the vortices more quickly.