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View Full Version : TACKING INTO THE WIND


Idahotom
03-09-2012, 02:13 PM
I have noticed a few times now, that when the wind is at 2:30 or 3, or 10:30 to 9 (with straight ahead being noon) that contrary to common sense (as there is for sure a head wind component, or at best a direct cross, but for sure no tailwind push) my ScanGauge shows better mileage then normal. I won't mention specific MPG's, but suffice it to say that all things taken into consideration for the stretch of road I'm on, the speed I'm goin, and the load I'm carrying, the MPG is higher then normal.

Now this got me thinking, and I'm not claiming this is happening, just throwing it out there as a theory for others who drive like me (eyes glued to the SC). There is a possibility the Yaris HB somehow develops a little lift, or at least less drag, when the wind hits it at an angle......don't call BS please, it doesn't really make sense to me either! But, as I have noticed this more then once, or at least have seemed to, I plan to see if it occurs again. It would be a bit of dumb luck on Toyota's part if so, not even they are that good! So, just a heads up the next time you have a good x-wind on a straight road, with flags and other wind indicators to eyeball as you drive, see if you notice anything unexpected.

My other "blizzard" posts, with some pretty good mileage for winter driving and a lot of first and second gear through slush, MAY have been an indication that this is happening. It wasn't just a little breezy, but a gale, 30 to 50. If nothing else, this would be a good rumor to start about the Yaris:w00t:

Uber_Otter
03-13-2012, 04:16 PM
Most highways are bermed up on the sides, with the wind coming from the sides the berms will push the air up and created a big vortex for you to drive through as it rolls over the road. I fly RC planes and there is a berm next to the runway. Its pretty noticeable change in air 5 foot off the ground.

SailDesign
03-13-2012, 09:37 PM
I have noticed a few times now, that when the wind is at 2:30 or 3, or 10:30 to 9 (with straight ahead being noon) that contrary to common sense (as there is for sure a head wind component, or at best a direct cross, but for sure no tailwind push) my ScanGauge shows better mileage then normal. I won't mention specific MPG's, but suffice it to say that all things taken into consideration for the stretch of road I'm on, the speed I'm goin, and the load I'm carrying, the MPG is higher then normal.

Now this got me thinking, and I'm not claiming this is happening, just throwing it out there as a theory for others who drive like me (eyes glued to the SC). There is a possibility the Yaris HB somehow develops a little lift, or at least less drag, when the wind hits it at an angle......don't call BS please, it doesn't really make sense to me either! But, as I have noticed this more then once, or at least have seemed to, I plan to see if it occurs again. It would be a bit of dumb luck on Toyota's part if so, not even they are that good! So, just a heads up the next time you have a good x-wind on a straight road, with flags and other wind indicators to eyeball as you drive, see if you notice anything unexpected.

My other "blizzard" posts, with some pretty good mileage for winter driving and a lot of first and second gear through slush, MAY have been an indication that this is happening. It wasn't just a little breezy, but a gale, 30 to 50. If nothing else, this would be a good rumor to start about the Yaris:w00t:


Assuming you are doing 50 or so, with the wind at 9:00, it would have to be really strong to be anywhere close to further aft than 10:30 or so. With you doing 50, and the wind also at 50mph from dead sideways, the apparent wind (what you would feel if you stood up out of a sun-roof) could only be at 45 degrees from your heading.
I'm not saying you're imagining it, but I don't think the Yaris would develop forward lift from that apparent wind.

Idahotom
03-17-2012, 11:49 AM
Thanks for the considered aerodynamic responses, and not immediately calling BS!
I really hesitated to even make the initial post about the so-called tacking effect in high, very high, cross winds, and only did so after repeated occasions of what seemed to be just that. Interesting that the two responses were from a model airplane pilot and a sailor!

I should mention that I fly a homebuilt aircraft (Rans S-7S), and much more then most keep a close eye on the wind and it's effect, even while driving. Also, both of my blizzard drives (with the surprisingly high mileage as reported by the SG and at fillup) were along routes I regularly fly at a very low level.

As of now in the future I'll ascribe the effect to some sort of partially unexplained vortex lift/lesser drag caused by a combination of road berming, and low relative headwinds caused by very high crosswinds. And they were reported at up to 70 mph that day, though I feel in the areas I was in they were more like high 30's to low 50's, I'm an old hang glider pilot also.... I do know the Yaris seems to coast better then anything I've ever driven, low rolling resistance aside, it seems to be very low drag also. Winds like this are not that uncommon here, I'm sure I'll have the chance to play with the situation again, something to do while driving in bad weather anyway!

eTiMaGo
03-17-2012, 12:08 PM
next step: fit wings to your Yaris :D

bentjazz
03-17-2012, 12:23 PM
Don't know about this subject, but I wouldn't mind living in Idaho. Lots of open space, unlike the sardine packed area I live in.
Lots of libertarians out there from what I hear, too.
Oops, this isn't Yaris related, is it?