When does the greatest wake turbulence strength occur?

The greatest wake turbulence strength occurs when the generating aircraft is heavy, clean, and slow. This is because wake turbulence is primarily produced at lower speeds during specific configurations of the aircraft (like clean configuration) and, most critically, when the aircraft is at its maximum weight.

When an aircraft is heavy, its wings create a more significant disturbance in the air, resulting in stronger vortices. Additionally, when the aircraft is clean (meaning the landing gear and flaps are retracted), it experiences enhanced aerodynamic efficiency, which further contributes to the generation of more substantial wake vortices.

Flying at slow speeds increases the duration these vortices remain in the air, since the aircraft does not generate as much lift, allowing the wake to linger for a more extended period. Understanding this phenomenon is crucial for maintaining safe separation distances behind heavy aircraft during operations, particularly during takeoff and landing phases.