English: The effect of the installation of Winglets on the wing of a Boeing 737 NG. The color represents the amount of rotation present in the air immediately behind the trailing edge. Specifically, the data represents the quantity ${\displaystyle Vorticity\times {\frac {span}{V_{\infty }}}}$ with values ranging from to

Data measured at M=0.78 & lift coefficient=0.5 . The winglet-less measurement was made at a higher angle of attack (2.55°) than the winglet case (2.43°). Quantitative data is loosely interpreted from a Boeing magazine publication.

It can be seen that the presence of the winglet distributes the vorticity more evenly along the outer part of the wing.