Portland to Florida trip round 2

[Phase]

Tail wind from Arizona to Salt Lake City and I got crazy numbers. Just fun to see. Not every day conditions. Lots of traffic flowing fast too for summer travelers. So tail wind combined with corridor effect

Barely had to put foot on throttle and sometimes had to take it off

I’ve experienced a weird phenomenon where it seems like I get better mpg and use less throttle when I have a tailwind and go FASTER, than if I go slower. My mpg actually decreases and I have to use more throttle if I drop down from 85 mph to 75 mph. It’s hard to explain. Maybe something to do with extreme low drag conditions and momentum carrying me forward more?

[Phase]

So we’ve all seen these angled in box cavities I’m sure on semi trucks

[Phase]

But this is the first time I’ve seen only side cavity fins. They look a bit janky but I’m assuming they do better than nothing?

[freebeard]

Maybe they keep the back doors clean? Like the dust deflectors on 1950s station wagons?

[Phase]

Originally Posted by freebeard

Maybe they keep the back doors clean? Like the dust deflectors on 1950s station wagons?

I looked up the rocket tail manufacturer website. Their claim is that the side wings reduce drag by 3-4 percent. No idea what the translates to in the semi truck world. But either way, reduced drag

[aerohead]

Originally Posted by Phase

But this is the first time I’ve seen only side cavity fins. They look a bit janky but I’m assuming they do better than nothing?

What's curious about Rocket Tail is that, if you go to their website and look at the original 'research' it includes an upper 'wing', spanning the width of the trailer roof.
None that I see at truck stops have this upper wing.
Buyer beware!

[Phase]

Originally Posted by aerohead

What's curious about Rocket Tail is that, if you go to their website and look at the original 'research' it includes an upper 'wing', spanning the width of the trailer roof.
None that I see at truck stops have this upper wing.
Buyer beware!

I mean I can still see the side fins being effective. Maybe not as high as their claims, but remember I did something similar with my ioniq during my Seattle road trip and then a week later driving from Portland to Alabama. My mpg seemed to increase a few points. I’ll be making permanent versions with abs plastic and machine screw drilled them into place with extra 3m double sided tape to reinforce the attachment so they will stay on during extreme storms and conditions and car washes

[freebeard]

I’ll be making permanent versions with abs plastic and machine screw drilled them into place

Rivet nut
A rivet nut, also known as a blind rivet nut, or rivnut, is a one-piece internally threaded and counterbored tubular rivet that can be anchored entirely from one side. It is a kind of threaded insert. There are two types: one is designed to form a bulge on the back side of the panel as a screw is tightened in its threads. The other is similarly drawn in using a screw, but is drawn into the sleeve instead of creating a bulge.
More at Wikipedia

[Piotrsko]

Originally Posted by aerohead

What's curious about Rocket Tail is that, if you go to their website and look at the original 'research' it includes an upper 'wing', spanning the width of the trailer roof.
None that I see at truck stops have this upper wing.
Buyer beware!

What with the damn overpasses not really being marked anymore why would anyone want to increase their trailer height especially unladen?

[freebeard]

www.ttnews.com: New Technologies Target Trailer Efficiency

This article calls out

• TruckWings, a device that reduces the gap between tractor and trailer during on-highway travel.
• The well known TrailerTail rear-door aerodynamic device from Stemco [discontinued]
• the Rocketail Wing showed 3.3% to 3.6% efficiency improvements.
• Utility Trailer, whose USS-120A side skirt is standard on its refrigerated and dry van trailers, this year introduced its Utility Aerodynamic Tail.

Sometimes the old ways are the best


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