Probably a stupid question. I was looking at the black/white version. Reminds me of an Orca. Which in turn raised a thought. Fish have a dorsal fin. Turns out that some fighter jets do as well.
From what I read, increases side slip angle" and "At high side slip angles, it produces stable vortices along the surface of the vertical tail which produces higher suction force over vertical tail, thus increasing the side force." (not a huge one)
Ok. I dont understand all that. Sounds good though. More stable, increase increase cooling surface area, and house some electronics. But it would add to cost, and people would probably not like the looks of the fin.
The San Jose Sharks should buy this one :-)
Somebody should make a vinyl wrap to do this! If you listen to the call with one of the engineers, it was designed like a shark's aerodynamics.
I was thinking a little longer and shorter. Then maybe curving it so we can put solar panels on it (if at all effective). You can fill in the spaces or keep it saw tooth like this
Note that I also changed the Widow so that the black area is not so obstructive to vision. I gave up on trying to make a decent wave on that. Shows the idea though. It could curve down a little, whatever gives better vision. Or just be straight.
"At high side slip angles, it produces stable vortices along the surface of the vertical tail which produces higher suction force over vertical tail, thus increasing the side force." They're talking about a tapered tail, a "fin" that is connected to a larger vertical tail. This makes the vertical tail (vertical stabilizer) more effective. A fin by itself doesn't do anything. The Aptera does have a vertical stabilizer but it's under the vehicle, i.e. a ventral fin. At least, I suspect that's why the wheel skirt is so large - to make the vehicle aerodynamically stable.
@Ken Kobayashi
Thank you very much for the clear explanation. Do you also have a force parallelogram to illustrate the force ratios on the Aptera.
It's just a matter of having the center of aerodymaic pressure behind the center of mass. This video is about rockets but the principle applies to road vehicles as well. https://www.youtube.com/watch?v=GyDn_trULaE