[aerohead]

Originally Posted by maczo

Hi,

I recently talked with a person that said keeping roof racks mounted on 2 square-backs (VW Transporter, Chrysler 300C) actually had positive effect on fuel economy.

The person happens to be a trained pilot and knows a bit about aero (started explaining to me how the back, not front, is important contrary to common belief). When asked how exactly having the roof rack on (specifically the back part) would be able to help, the answer was a shrug - no idea how that would be possible except for unforeseen interactions with the wake; but the numbers are apparently undeniable.

Soo does anyone here know of any way this could actually be true? Or is this just a case of biased observations?

I've not seen any evidence of it in 45-years of looking.I've seen a lot of evidence to the contrary.