This isn’t a computer-generated image. It’s an actual picture of what happened when NASA decided to test the air flow around an F-18 by putting a model plane, and a lot of dye, in a water tunnel.


These images were created at the Dryden Flight Research Center, back in 1985. Specifically, they were created in the Dryden Water Tunnel. NASA had a procedure for simulating, and visualizing, the flight of a air craft without endangering the air craft:


The procedure is used to check for vortices, swirls of air that might drag the plane back or knock it around.


Images: NASA Dryden Center