09-25-2011, 01:54 PM
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#1 (permalink)
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Master EcoModder
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positive Semi sighting!
While enjoying a recent roadtrip, I spotted a semi-trailer outfitted w rear aero aids!
I was cruising west on I-90 in Montana at my usual 50mph., when this one special nationally known company rig (Swift) blew by me.
I couldn't get to my camera fast enough, nor was willing to crank it up to 60-65 to catch up w him/her?; but will try to describe.
Simply put, what I saw was like a cardboard box sans its floor mounted horizonally on the back of the '53 trailer. There wasn't much taper on the sides to mimic any funnel look. At the most, I would estimate only 2-3 degrees inward.
The top, and bottom "flaps" were made different. The top, and the bottom flaps were both 2 piece affairs, with a slight gap directly in the middle.
I was so shocked to see this out of the blue, that I don't remember what type of rear door/doors that this trailer has.
I can only surmise that if it had a rollup type door, and if loads were on conventional pallets, ( which would be 2 side by side covering the entire interior trailer width) the aero aid could stay permanent as long as the rig stayed in the western states. ( trailer length laws)
I estimate that the extension length to be somewhere around 3-4 feet long!
I could be wrong, please correct me if I am; but I sort of associated the Swift company name to be part of the group of companies that generally hire "newbie" drivers such as JB Hunt.
That's why I was surprised to see this effort under that company banner, but non the less; applaud the effort!
It's certainly no where near a boattail, so I wonder what the mpg. change is worth.
Though far more common, it's also interesting to me to see the moving companies like Atlas in particilar that have the rounded fiberglass extensions with custom taillights. I'm sure it's mainly meant just to stuff just a little more load on, but it appears that mpg. wise, it might help a little bit!
It would be interesting to hear from someone in that industry that would know the facts!
Aloha!
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09-25-2011, 02:01 PM
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#2 (permalink)
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Master EcoModder
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I've seen these around.
Swift wouldn't be doing it without tangible MPG benefits.
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09-25-2011, 03:54 PM
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#3 (permalink)
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Tenderfoot
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Did'ya see this??

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09-25-2011, 04:42 PM
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#4 (permalink)
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Master EcoModder
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Or like this?

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09-25-2011, 05:15 PM
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#5 (permalink)
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60+ mpg at posted speeds
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Quote:
Originally Posted by Big Dave
Swift wouldn't be doing it without tangible MPG benefits.
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Yup. Could also be that these are test trailers... trying to prove the benefit in their own fleet with their own drivers on a small scale first. ??
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09-25-2011, 05:38 PM
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#6 (permalink)
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Pishtaco
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They're proven aerodynamics. Link 1. Link 2. Google semi aerodynamics.
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09-25-2011, 09:39 PM
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#7 (permalink)
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Master EcoModder
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Orbywan, this would be perfect for your RV !
Has anyone seen one of these in real life ?

Last edited by JasonG; 09-25-2011 at 09:52 PM..
Reason: Bad pic link.
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09-27-2011, 08:49 PM
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#8 (permalink)
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Master EcoModder
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Thanks for sharing the pics. What Chaz posted is the closest to what I saw.
I'm happy to report I saw tons of rigs with some kind of trailer side skirts!
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03-17-2012, 04:50 PM
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#9 (permalink)
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Master EcoModder
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my 1st sighting
I saw my 1st Trailer Tail heading south towards Dallas on I-35 day before yesterday.
I almost 'missed' it as it was not deployed,but rather stowed on the back of a semi,doing 63 mph into a 20 mph headwind.
I kept watching to see if the driver was going to deploy a parachute in an economic wrist-slitting move,but couldn't hang around long enough to watch.
Strange.Very strange!
Autospontaneoustesticularatrophobia I think. 
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03-18-2012, 09:01 AM
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#10 (permalink)
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Master EcoModder
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Probably broke it backing up to a warehouse door.
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