Aero luggage

[robchalmers]

Does anyone make a 'backpack' for hatchback that could double as a kammback??

[aerohead]

Originally Posted by robchalmers

Does anyone make a 'backpack' for hatchback that could double as a kammback??

First,let me admit that I don't keep my head to the rails as far as the market goes,but so far,I've not seen any purpose-built packs tailored specifically for any particular vehicle.
And that would be a mandatory requirement for the proper function of a Kamm-form.
And due to the myriad sizes and shapes of hatchbacks,it would be prohibitively expensive to enter the game.
Consumer choice and lack of any industry rationalization becomes the double-edged sword.

[Rokeby]

You might check out AeroPACK Cargo Carriers

FWIW, it doesnt appear that it would work on a Prius due the suspension
straps pressing on the somewhat fragile rear spoiler.

Here's a German version that appears to be better engineered.

In either case, I doubt that it would enhance aero.

At best, when rigged on the back of the vehicle, they wouldn't degrade
areo very much.

[Tango Charlie]

Here's a sketch of an idea I had awhile ago. Thought an aerodynamic luggage carrier for my Vibe could be made from 1/4" paneling, using "stitch and glue" process.



Was this what you had in mind, or were you thinking more of something that would sit behind the vehicle, like a hitch receiver-mounted thing?

[Piwoslaw]

Originally Posted by Rokeby

You might check out AeroPACK Cargo Carriers

Here's a German version that appears to be better engineered.

In either case, I doubt that it would enhance aero.

At best, when rigged on the back of the vehicle, they wouldn't degrade
areo very much.

The AeroPack claims fuel savings of 15%-25%! So it's better than a full boattail (15%)? Yeah, right.
The pictures on the German version also show how it doesn't mess with the airflow, but only on the Lupo, where it is mounted pretty low. On the other pics it's mounted way up in the airstream, acting like a spoiler or parachute.

Each time I look at my Kammbacked car (only 10-30 times per day) I can't help thinking how much more space I'd have if the rear window was moved to the end of the extension. I'm thinking more and more seriously about fabricating a Kammhatch.

[robchalmers]

those would do!

I've been toying with the idea of a detachable Fibreglass Kammback that doubles as a extra storage space. with the chunky styling of the polo it could be relatively 'easy'

the only reason I'd have it detatchable is so that the insurance would see it as a temporary addition and not a modification

[DonR]

[QUOTE=Piwoslaw;175376]The AeroPack claims fuel savings of 15%-25%! So it's better than a full boattail (15%)? Yeah, right.
QUOTE]

They state that a roof top cargo carrier increases fuel usage by 15-25%. By using the pack, Which has "no drag" you gain that back. One mfg. of these packs posted here that they were seeing what I remember as a .5-1% increase in MPG. I don't think they quoted that on their website though.

Don

[mikel09]

To clarify: AeroPACK mounts on all hatch backs or lift gates and is made in USA. It does mount on a Prius with a short spoiler.

Roof mounting gear with a box, basket or racks creates a 17% to 25% mpg loss (Consumer Reports test data) depending on car and speeds. Edmunds performed a similar test and reported a 21% mpg loss with roof mounted gear.

AeroPACK when loaded, reduces eddy currents behind the vehicle. Some customers have reported mpg improvements, we make no guarantee.

It is much easier to load than climbing on the roof. Contact me at support@aeropackusa.com There are lots of happy AeroPACK owners.

Cheers....

[jamesqf]

The problem, though, is that if you put much weight back there, you mess up the car's weight distribution, and therefore the handling.

Why not a small trailer instead?

[robchalmers]

quite happy to have extra weight out back as a trailer may hinder the corner performance or atleast my confidence on the limit :P