Wind Wedge and Wind Tunnel Designs

julia wrote:

> Several years ago, we purchased a "wind wedge" air deflector (for a
> pickup pulling a fifth wheel), but I can't recall the manufacturer.
>
> We've gotten a new truck and would like to get a new mount for the
> deflector.
>
> Does anyone know who sells mounting kits for wind wedge air deflectors?
>
> I've found "wind-tunnel-designs.com" on the web. Some of their
> graphics look similar to our wind wedge.
>
> Does anyone have experience with the Wind Tunnel Designs company (from
> Woodland, WA USA)? Are they reliable?
>
> (I posted this a few weeks ago but got no replies - maybe because it
> was over a holiday weekend. So, I'm trying again.)
>

I usually ignore this subject when it comes up, but can't help myself today.

Less than 20% of our total miles are spent towing the fifth wheel. If a
wind deflector improved mileage by 20% when towing, it would still be an
overall loss unless we removed it when not towing. I haven't seen
anything to indicate that large a gain, and I have yet to see anyone
remove a deflector while in a campground. Most drive around with the
damn thing acting like a parachute when the trailer isn't attached.

Isn't this another one of those things which men buy from "Big Dicks
Truck Accessories?"

I understand them on over the road trucks. I don't on pleasure trucks.

Lon

I see where Lon VanOstran <RVnFT@wmconnect.com> contributed:

>Less than 20% of our total miles are spent towing the fifth wheel. If a
>wind deflector improved mileage by 20% when towing, it would still be an
>overall loss unless we removed it when not towing. I haven't seen
>anything to indicate that large a gain, and I have yet to see anyone
>remove a deflector while in a campground. Most drive around with the
>damn thing acting like a parachute when the trailer isn't attached.
>
>Isn't this another one of those things which men buy from "Big Dicks
>Truck Accessories?"
>
>I understand them on over the road trucks. I don't on pleasure trucks.

I think Lon is mostly correct. Properly-installed wind deflectors on
big rigs DO produce measurable results. IIRC around 5% improvement,
(no WAY 20%) but more than enough to pay for them in commercial
service.

HOWEVER, they only produce credible savings when correctly installed,
close to the trailer at the ideal angle and height. If not they will
actually be detrimental, creating additional drag rather than reducing
it. Not to mention that they definitely create extra drag running
bobtail, and on pickups create a mounting problem.

Count me as a firm opponent. I suggest the OP find a sucker who wants
their old sail, and fergeddaboudit.

Will Sill
The Curmudgeon of Sill Hill