air tabs

[K-Man]

Hey Guys

Do the air tabs actually work in reducing drag and improving MPG or is just wishful thinking. you need a ton oh them acccording to the web site (AMAZON) @ $2 or so each,
any experience K-man

1995 falcon intervec

[gerrym51]

i've read about these in the past. a vans surface area is already small. i doubt use on a van would at best be negligible improvment

[K-Man]

thanks jerry

That's what I was thinking but i wonder if this is a scientific thing or voodoo magic.

[SiennaGuy]

If these small tabs work, then logically the 1959 Cadillac with its huge tailfins would handle like a dream.

[mikes47]

Here is a video about the science:

http://www.youtube.com/watch?v=V13T_hSSlGY

And some pics of Sprinter Vans Air-tab equipped: http://www.airtab.com/gallery/vans.html

[avanti]

Well, if there was any actual science in that video, I missed it. That said, Airtabs are just vortex generators, which are very commonly used in aircraft design. I have tended to be a skeptic about stuff like this, but the principal is sound. NASA claims Airtabs as a "spinoff" of their research:

http://spinoff.nasa.gov/Spinoff2008/t_3.html

which is a little closer to "science", although not exactly from a disinterested source. My best guess is that they DO work, but the size of the effect, if actually measured in a rigorous study would probably disappoint. I have tried and failed to find such a study of real-world applications of Airtabs that was scientifically convincing. Not surprising. Who would fund such a study?

[Bruceper]

There are a few videos on YouTube about AirTabs. So far I'm not impressed. The AirTab website has a pdf of a "test" they did where a semi truck achieved 0.15 mpg better with airtabs. They have another test that achieved 0.16 mpg better.

1) Lets just say fuel is $4 per gallon (I'm Canadian, I'm just guessing on US fuel prices!)
2) Assume your motorhome got 10mpg

In order to break even after buying AirTabs you would need to drive approximately 40,000 miles and burn 3940 gallons of fuel. That's a lot of driving, and I'll guarantee you wouldn't notice the fuel savings. On a fleet of semi trucks that put on 100,000+ miles a year? Maybe.

Additionally, If your fuel mileage was higher than 10 mpg, it would take longer to achieve actual cash savings.

They do talk about other advantages, and those might be worthwhile. But if you're thinking you're going to save a ton of fuel, don't bother.

As a note, their PDF has some strangeness too. If it was truly to be a real world test, why would they run the test without AirTabs, make their measurements and then not refuel the vehicle to the same volume for the second test with AirTabs? Less fuel equals less weight which means less energy required to move it which equals better fuel economy. Granted it's not much weight, but this brings into question the fairness of their tests.

[avanti]

I wouldn't believe anything less than a blind study in which the drivers didn't know whether or not the vehicle had the tabs. This is what is known as "science".

[Davydd]

The real question. Do you think they would make your B look sexy and cool if you put them on?

[SiennaGuy]

How's this?



(OK, I'm feeling a bit silly tonight)

[K-Man]

I like the red job. Looking for investor?

[Aeronie]

Originally Posted by SiennaGuy

How's this?



(OK, I'm feeling a bit silly tonight)

Now that's just plain sexy.