[donee]

Hi Unchosen...,

I think you need a Chirp CW radar for that application. A pulse radar would need to be expensive to have the range gates as small and as often as needed. I would avoid drafing without such an aid. But to be sure it works, you will need a test track and a willing lead car. The new Prius has an optional radar cruise control. Also, that 77 GHz stuff is kinda expensive in small quantities.

Hi Delta...,

I remember that. They showed a car drafting a big rig that was not even Wayne driving it. They used a sly technique to imply that it was Wayne. They were talking about the Insight, while the Saturn SL was there on the screen tail gating the semi. Wayne was in the area to demonstrate Insight techniques, and the short bit with him was in an Insight.

Hi All...,

In the Prius, it gets best mileage when its going along very stable-y at about 53 mph. When a Semi comes up next to it, the bow wave will drop the speed 1 mpg, which drops the mileage from about 72 to 65. Once you get back up to 53 mph, you can then feather back the throttle and have it lope along at 72 mpg again. The main problem is the sideways wind flow is like a cross wind. Which increase the aero drag. Along the side of the truck, the boundary layer of the truck is so low-energy, that its turblent, and screws up the Prius aerodynamics. And the Prius has such good aerodynamics it does not get much benefit from astern drafting at 65 mph (what trucks do around here in the 55 mph zones), that I just stay at 53 mph in the far right lane. If I see a truck coming up along side, I get way over to the right to avoid most of the bow wave and turbulent side air.