Full-boat-tail trailer with gap-fillers for Toyota T-100 pickup

[aerohead]

Originally Posted by skyking

Darn.
I have a camping weekend starting Thursday the 12th. I'd have to book on home the 10th to make that.

Then you'll have a great camping trip and we'll find another time to get together!

[aerohead]

Since the rooftop cab-wing delivery to Gilkison trip and the Bonneville trip, I've had a chance to compare some of the logbook entries with that of the Viking trip data.
It appears that Viking is heavy enough that it will cause an overspeed bias during two-lane highway mountain descents.
Typically,without the trailer, closed-throttle engine braking is sufficient enough to control downhill speed during mountain driving.
With Viking,I am forced to use the brakes at times to keep at posted limits which burns off valuable kinetic energy.
Where I expected my highest mpg(82-mpg with the CRX),on the run from Cloudcroft to Artesia,New Mexico,I actually suffer about an 8-mpg penalty,falling from an indicated 39-mpg(without Viking),to 31 mpg(with), both to braking ,and also lifting on the uphill gradients.
This might not be so much a liability with regenerative braking on an EV,but as an 'overbuilt' and 'overweight' camping trailer one might want to favor interstate grades.
The lightweight boat-tailing is really showing positive gains with the T-100 ,so I think it's prudent to say that we can take that technology all the way to the bank.However,unless I put Viking on a pretty radical weight-loss diet,I'll never see its full potential unless I keep to the flatlands.Which kinda defeats her purpose.
Once I get the A2 Wind Tunnel trip behind me I'll have energy to spend in that direction.
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Braggarts of the future: "Mine's smaller than your's!"

[BamZipPow]

Do you happen to know/estimate the trailer's current weight?

[aerohead]

Originally Posted by BamZipPow

Do you happen to know/estimate the trailer's current weight?

On the last outing she weighed in at 720 lbs.And that was with an incomplete gap-filler mechanism.
What I ought to do is start from scratch.Or at least reconfigure Viking's body to actually match the aft-body of the T-100,then do a plaster splash of that in which to layup a lightweight shell.
If I went that far,I could lose all the steel superstructure underneath and it would also push the nose and sides out such that the gap-filler panels could be shorter and lighter.
There's no reason why the trailer should weigh any more than 200-lbs(91-kg).
It would require vacuum-formed thermoplastic shells(top and bottom) and composite gap-filler mechanism.Pre-preg Carbon-fiber epoxy would be nice!
If I live long enough I'll get around to all of it.
An inflated tail would be the lightest of all.But I was thinking about how to help plug-in EVs with their limited range issues.A LEAF or MiEV @ Cd 0.12 and double the Li-ion pack would be interesting.Or pull a gen set in it for a 'holiday-only" hybrid.
There are no shortages for aerodynamic challenges!
Oh yes,Welcome to the 35-mpg Club! That's great!
Next meal's on me.

[euromodder]

Originally Posted by aerohead

It appears that Viking is heavy enough that it will cause an overspeed bias during two-lane highway mountain descents.

It need not be just the weight ...

You could see the weight and aero improvement actually working against you, resulting in a higher terminal velocity as drag is reduced while weight is increased ...

[aerohead]

Originally Posted by euromodder

It need not be just the weight ...

You could see the weight and aero improvement actually working against you, resulting in a higher terminal velocity as drag is reduced while weight is increased ...

Thanks!
That's funny!
I've obviously been so attached to a weight prejudice when staring at the data that the drag component fell into the background.
Ah yes,age,isn't it a wonderful thing!
If the Viking body weren't bonded,I could have remove it and ballasted the chassis of it to the all-up weight and tested for the rolling resistance affect on mpg and downhill behavior for comparison.
It's tough having more than one variable.
And the A2 load cells can't take on a vehicle over 4,400-lbs so I can't test Viking there.Rats!
I appreciate the second set of eyes.
Looks like it may take a village to streamline!

[aerohead]

My apology to any members following this thread.I wanted to toss out some thoughts about Viking's future.
*Bonneville was kind of a bust.One mile is not enough to achieve terminal velocity.And since I never got out of 4th gear,I don't even know what the truck will do.
*So it doesn't make any sense to consider running Viking on the salt.With such low power I'm sunk as far as top speed goes.
*And Viking is heavy enough that it would exceed the weight limit for the load cells at the A2 Wind Tunnel,so there's no future in dragging it to North Carolina either.
*That leaves Plan-Z.I'll work on the honey-do list for the femme-bot until April,then work from then until September to complete the boat tail on the T-100.
*I'll create a faux 1-wheel undercarriage which I can attach under the tail at A2 with which to simulate a properly integrated,body-in-white,gap-filled,1-wheel trailer like I never finished for the CRX.
*With this configuration I'll be within the weight limit for A2 and we'll be able to measure the drag for the truck/'trailer' combo.
*Since they have a smoke-generator we'll be able to video record the airflow for You-Tube as so many other members have done.
*If I can get this far,we should have a sense of real world numbers for a proper gap-filled trailer application.And see how it jives with predictions.
*Then afterwards,I can complete the Viking project at my leisure.
*Anyway,thanks for hanging in there,and I'll check back in as things evolve.

[orbywan]

Originally Posted by aerohead

My apology to any members following this thread.I wanted to toss out some thoughts about Viking's future.
*Bonneville was kind of a bust.One mile is not enough to achieve terminal velocity.And since I never got out of 4th gear,I don't even know what the truck will do.
*So it doesn't make any sense to consider running Viking on the salt.With such low power I'm sunk as far as top speed goes.
*And Viking is heavy enough that it would exceed the weight limit for the load cells at the A2 Wind Tunnel,so there's no future in dragging it to North Carolina either.
*That leaves Plan-Z.I'll work on the honey-do list for the femme-bot until April,then work from then until September to complete the boat tail on the T-100.
*I'll create a faux 1-wheel undercarriage which I can attach under the tail at A2 with which to simulate a properly integrated,body-in-white,gap-filled,1-wheel trailer like I never finished for the CRX.
*With this configuration I'll be within the weight limit for A2 and we'll be able to measure the drag for the truck/'trailer' combo.
*Since they have a smoke-generator we'll be able to video record the airflow for You-Tube as so many other members have done.
*If I can get this far,we should have a sense of real world numbers for a proper gap-filled trailer application.And see how it jives with predictions.
*Then afterwards,I can complete the Viking project at my leisure.
*Anyway,thanks for hanging in there,and I'll check back in as things evolve.

You're a busy guy Phil. : ) Can't wait to see the finished boat tail on the T100 and see the trailer finished. I read somewhere there the trailer weighs 750 pounds, is that because the original boat hull was so heavy?

I'm working on some front mods and wheel pants for the Aero RV but there just isn't any free time lately. After those two items are finished I'll test it again and see where it's at. I'm considering rebuilding the boat tail to conform more to the template you guys are always talking about.

I know everyone thinks the current shape is all wrong but it made such a big improvement I'm not sure reshaping it to the template would make much of a gain. Would you hazard a guess on that one? Thanks.

[orbywan]

Originally Posted by aerohead

My apology to any members following this thread.I wanted to toss out some thoughts about Viking's future.

You're the last guy on planet that needs to apologize for anything as much as you contribute to this realm.

[aerohead]

Originally Posted by orbywan

You're a busy guy Phil. : ) Can't wait to see the finished boat tail on the T100 and see the trailer finished. I read somewhere there the trailer weighs 750 pounds, is that because the original boat hull was so heavy?

I'm working on some front mods and wheel pants for the Aero RV but there just isn't any free time lately. After those two items are finished I'll test it again and see where it's at. I'm considering rebuilding the boat tail to conform more to the template you guys are always talking about.

I know everyone thinks the current shape is all wrong but it made such a big improvement I'm not sure reshaping it to the template would make much of a gain. Would you hazard a guess on that one? Thanks.

Yep,she's plenty heavy!
HALLIBURTON and Slumberger did seismic shots over the original Viking boat hull and the Troposphere showed a large pool of oil there.So I thought she'd be an okay 'project' boat based on her curves.The thick fiberglass was a turn-off,although in light of losing the original aeroshell to goats,the added strength had some allure.
The trailer she's bonded to is actually the original boat trailer she came on (much more robust than an entry level utility trailer kit) and while very strong,sure taxes with high mass.
By the time I got the major gap-filler mechanism cobbled together the weight had really grown to black-hole status.
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I'd never do it again,although I could conceivably cast split molds off the finished body and lay up a lighter shell to bond to a lighter trailer.The compound curves are terrifically strong for wall section thickness.There's no reason for the entire trailer to weigh more than 200-lbs.And it would be strong enough to carry a second battery pack for a plug-in EV,or a gen-set for same,as a range extender.
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I've camped in it.And it would be safe for Grizzly territory at Yellowstone.It's a bit like a rigid tent.With a PV,charge controller and battery she'd make some nice white noise while moving air for restful sleep.