Airtabs?

[mass-hole]

So I did a search on Airtabs(these things: https://www.airtab.com/index.htm) here and most of the posts are fairly old and don't say much.

I've seen a lot of reviews which are extremely positive in regards to them stabilizing trailers in crosswinds or with passing semi's, neither of which I have an issue with, but am curious about any MPG advantage they might give? Some reviews mention some gains, but I imagine that's a hard thing to quantify with how variable conditions can be while towing(head winds, temperatures, hills, weight etc)

I am generally towing on 65+ mph freeways and often have to contend with 10+ mph headwinds. My fuel economy is often sub-9 and even into the 7's on bad days. just wondering if these might help a little due to high speeds I am usually traveling at with the headwinds.

[DocBrown]

I think this is based on a similar principle to the dimples on golf balls. In theory it looks great. The price actually isn't bad. You could probably do a trailer for under $300. If it works it would be interesting to see what the ROI is.

https://buyairtab.com/installation/

[mass-hole]

Originally Posted by DocBrown

I think this is based on a similar principle to the dimples on golf balls. In theory it looks great. The price actually isn't bad. You could probably do a trailer for under $300. If it works it would be interesting to see what the ROI is.

https://buyairtab.com/installation/

Yeah I think It would work out to $175 for me or something like that. My math said I needed 64 of them at 2.75 a piece

[hoppers4]

If your biggest concern is mpg, you won't be able to notice the difference except through wishful thinking. You'll never recover the cost.

[TaftCoach]

Originally Posted by hoppers4

If your biggest concern is mpg, you won't be able to notice the difference except through wishful thinking. You'll never recover the cost.

Over the past five years I’ve spent annually an average of $2,500 in fuel while towing. I found their claims of a 5% savings less than believable. At 2% the ROI four or five years. Plus cosmetically, meh. I’ll pass as well.

[mass-hole]

Originally Posted by TaftCoach

Over the past five years I’ve spent annually an average of $2,500 in fuel while towing. I found their claims of a 5% savings less than believable. At 2% the ROI four or five years. Plus cosmetically, meh. I’ll pass as well.

But there is also driving range and stress on the tow vehicle you can benefit from. It doesn't just need to be about the $.

But sure, yeah, thats why I asked. I am finding it hard to get any kind of really source on mpg's.

[Jay2504]

Kinda off topic, but I have wondered if an enclosed trailer underbelly helps with MPGs and how much if it does. Jay

[hoppers4]

Same difference as air tabs. MPG is already so crappy you'll never notice the difference.

[RedHorse1]

How many commercial highway trucks do you see with them?

[hoppers4]

Originally Posted by RedHorse1

How many commercial highway trucks do you see with them?

X2 - Excellent point!

[spoon059]

I'm with the majority here. If they were effective, you wouldn't be the first person thinking about it and there would be substantial information out there about them. If you want better fuel mileage, the easiest thing to do is slow down a little bit.

[D Cowley]

Originally Posted by hoppers4

If your biggest concern is mpg, you won't be able to notice the difference except through wishful thinking. You'll never recover the cost.

Exactly what Hoppers said. Perfect answer.

[muckinfuss]

It's all about your right foot! Everything else is high cost, low or no return.

[ARoamer]

Vortex Generators.
Experimental aircraft guys like them, and if you look closely at the big wind turbine blades, they are equipped with them also. But, I believe they are more for lift enhancement and lowering stall speeds when used in those applications. Wind tunnel data for use on Semi Trucks looks interesting though.

If you have a 3D printer you could crank out a bunch, a $15 2.2 KG spool of filament should do around 100+ of them depending on settings.
https://www.thingiverse.com/thing:2827019
Add a roll of double sided tape and you could go with the flow!

I'd try 'em but My DW would have a fit if I stuck them on our RV, even the command strips need approval....

[RedHorse1]

Might yield a significant MPG improvement if you tow at 110mph or better.
On a personal experience note, towed our X23B (23’, 4500#) with an Expedition 5.4 gasser and got 9mpg. Our 5th is 39’ and 13k# towed with a 350 6.7 and I get a solid 12mpg. The moral of the story is 3x the weight, 2x the length with a 30% increase in mpg? Go diesel! Use the little plastic fins to scoop your Frito Bean Dip.

Yeah, diesel fuel costs more but if this topic keeps you awake at night just drive a Tesla and stay in a Holiday Inn.

I hope I’ve offended no one with my post.

[LuckyDuck]

Originally Posted by RedHorse1

Might yield a significant MPG improvement if you tow at 110mph or better.
On a personal experience note, towed our X23B (23’, 4500#) with an Expedition 5.4 gasser and got 9mpg. Our 5th is 39’ and 13k# towed with a 350 6.7 and I get a solid 12mpg. The moral of the story is 3x the weight, 2x the length with a 30% increase in mpg? Go diesel! Use the little plastic fins to scoop your Frito Bean Dip.

Yeah, diesel fuel costs more but if this topic keeps you awake at night just drive a Tesla and stay in a Holiday Inn.

I hope I’ve offended no one with my post.

X2. And actually, here diesel costs about the same as regular gas and a lot less than the premium I have to use in my FR-S — and it sure can’t tow a trailer!

[ARoamer]

[QUOTE]=Might yield a significant MPG improvement if you tow at 110mph or better.[QUOTE]


Sorry if this post makes your eyes glaze over and makes you nod off....

Actually vortex generators, when used in aircraft and wind turbine blade applications, are applied mostly for low speed to keep airflow from separating from the lifting surface which lowers stall speed of the airfoil and increases low speed performance. But, on the other hand many large passenger jets have a vertical wing extension on each tip which is also a vortex generator and use smaller ones on wings and control surfaces.
https://www.boldmethod.com/learn-to-...ex-generators/
Airliners do use them see a greater than 1% reduction in fuel burn, and when you own a fleet of aircraft >1% can become a lot of fuel.
Boeing is developing a variable vortex generator and calculated-
"An airline flying 100 airplanes using these special vortex generators could save as much as 3 million gallons of fuel a year. That’s enough to take some 3,800 cars off the road for 12 months."
Australia did a study on a semi truck and found a 5-8% increase in fuel economy.-
https://roads-waterways.transport.ns...-generator.pdf

So.... They do work. How well they work depends on design and placement.

[us71na]

If you drove/towed a vehicle 100,000 miles a year at 10 mpg and they saved 1%, it would save you about 100 gallons of fuel per year. Very few of us tow or drive even 50K miles per year. YMMV

[Usmade56]

I have 2018 26xd class C. Drove it home from dealer towing my equinox and didn't drive it again until air tabs installed. What improved was stability when semi passed either direction and back of coach and toad cleaner because vacuum cleaner effect reduced. What did not change was mpg and side winds. After driving round trip Michigan to Arizona 2 times I spent a couple grand on sway bars, shocks and steering stabilizer and that improved cross wind driving. One other thing, I personally like the look on my coach. To each his own.

[Seann45]

If these really worked you would see all the semi's using them... I haven't seen one on a semi in years .... save your $$$ for your fuel tank...