2nd look at CYBERTRUCK

[redpoint5]

Surprising to see tailgate down is more efficient, as the common wisdom with trucks is that tailgate up is more efficient.

Also strange to see mirror delete made things worse.

[Vekke]

I think they did not adjust the frontal area change in mirror removal and lowering. I think they should then readjust their correction factors for the tunnel. I tried to ask that in the youtube comments there but no reply yet on that matter.

[aerohead]

If we had a side elevation technical drawing of CYBERTRUCK, with it's tailgate down, and superimposed the near-streamline's smoke trace ( shown in the video ) inside the 'vault'; in theory, this 'contour' that it 'describes', would become the 'first approximation' for constructing an 'ideal' roofline contour for the truck, compared to the simplistic, 'prismatic' shape that it possesses.
It might not be 'practical' as a pickup truck, but it would be 'aerodynamic,' as defined by Dr.-Ing. Wolf-Heinrich Hucho, in the preface of his 2nd-Edition, Aerodynamics of Road Vehicles.