When is the greatest vortex strength produced with regard to a generating airplane?

The greatest vortex strength produced by a generating airplane occurs when it is heavy, clean, and fast due to several aerodynamic principles.

When an airplane is heavy, it generates more lift to support its weight, which in turn increases the magnitude of the wingtip vortices. These vortices result from the high-pressure air beneath the wing spilling over the wingtips to the low-pressure area above the wing. The heavier the aircraft, the more lift it requires, leading to stronger and more pronounced vortices.

A clean configuration refers to the aircraft being free from drag-inducing devices, such as flaps or landing gear. This streamlined shape ensures that the airflow remains smooth and uninterrupted, allowing the aircraft to maintain a more efficient flight profile during which the structure of the vortices is more stable and pronounced.

Flying at a fast speed enhances the lift-to-drag ratio, resulting in a more significant and well-defined vortex. Speed increases the momentum of the air around the wing and contributes to the strength of the vortices generated.

In combination, being heavy, clean, and fast maximizes the aerodynamic conditions under which the airplane operates, leading to the production of the greatest vortex strength.