Question about drafting
 

I was driving north the other day and there was a 20mph wind out of the west. How would this effect drafting behind a big truck at a safe distance? Would the crosswind cancel any beneficial effects of the draft? Would it move the "pocket" to the east if we were both northbound? Anyone have any ideas?

The draft pocket would be moved to the east. I see similar conditions in my daily commute. I have a short piece of string taped to my hood where I can see it. This tells me the wind direction and wether the air is smooth or turbulent. This way I can see when I'm in the draft, and if I need to offset my car to one side of the lane or not. In very strong crosswinds I've gotten the best draft in the next lane over, similar to the formation that migrating birds use.

^ A piece of string in the hood???

Ok you have to elaborate you cant just say that and not post any pictures common that has to be something new here?!?!? :)

You take a piece of string, you attach it to your hood.

Complete 500 page installation and users manual available for only (6 easy payments of) $29.95!!!

I would just tape it somewhere near the middle of the hood, string going rearward. Only problem with my car, is I cant see the hood, at all! :eek:

Got an antenna or a hood ornament?

I got the idea from reading threads about tuft testing. The leading edge of a 5" piece of wool string is taped on various locations to observe airflow patterns. I taped a few in places that are visible to me while driving.

Here's a good "thread" (HAHAHAHAHAHAHAHAHAHAHAHAHAHAHA!!). https://www.gassavers.org/showthread....ight=tuft+test