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

[orange4boy]

It looks like this could easily be a 1-year project.I have to laugh at nyself for being so ignorant and naive to think I could just slam it all together in a period of 3-months and get it road-tested.

Projects like what you are working on are very hard to estimate. Even professionals have to guess. I can relate though.

You have to have goals even if they are unrealistic sometimes. If you knew when you started what what you know, now the project would probably not be nearly as far along as it is.

Good luck!

[aerohead]

Here's where she is as of this AM:

[aerohead]

Originally Posted by aerohead

Here's where she is as of this AM:

You can ignore the atomic blast image of Cd 0.85 house in Nevada desert.

[BamZipPow]

Nice...

What...no moon caps fer the wheels?

[orange4boy]

Looks good. Like a shark. Hopefully glides like one.

Good luck on your trip.

[aerohead]

Well I'm back home licking my wounds after my 'Burt Munro moment.'
I finally got away on Sunday,Dec.27 at 1:30 PM.I'd hoped to make it as far as Monahans,spend the night,and get into Las Cruces the next day to salvage the tail end of Gilkison's holiday time off from work.
At 7:45 PM,in Odessa,TX,at 350-miles( 564 km )and at 63-mph ( 100 km/h )and in total darkness,the driver side trailer wheel went it's own way,with the trailer crashing onto I-20.
Four lug bolts were gone,along with the wheel/tire and dust cap from the hub.
The lead and trailing fairing for the wheel were completely destroyed and spring fairing damaged.The bellypan was breached and rear outside corner of steel wheel well displaced inward and poised like a knife-edge over where the tire tread would have been.
I did have a spare,although unlike Burt,had no Ada,who could bail me out with the fairing and bellypan situation.
I had only two spare lug bolts and elected to stay overnight and search for some next day,as the 24-HR Super Wal-Mart had nothing to offer.
Monday's search was futile in the oil-patch capital of the world.Everyone tried to help,but no one could come up with what I needed.
I ended up robbing a bolt from the passenger side and limped home with 3-bolts per wheel.
The up-shot is that I "crashed" at 63-mph.The trailer was pulling so well,I'd intended to make the run next day between Monahans and El Paso at 80-mph.Had I lost a wheel at that speed it could have turned pretty ugly.
Here are some Data and Observations from the debaucle:
Temps--------- 37-degrees-to-42-degrees out,25-degrees overnight,mid-thirties-to-42-degrees on return.
Baro Press.: 30.20" rising-to-30.42" steady
air density ave.(rho) 0.002543 slugs ( 6.986 % higher than standard )
Wind: 10-15 mph NW at start,diminishing,calm-to- 5mph N at return
Warm-starts: 4-going,4-on return
Cold-starts: 2 @ mid-20s temps overnight soak
Elevation: 620-2,854-620-feet ( 189-871-189 meters )

Weight: Overall rig 4,620-pounds ( 2100 kg )
Forward 2-axles 4,080-pounds ( 1854.5 kg )
Trailer axle 370-pounds ( 168 kg )
Tongue weight: 60-pounds ( 14 % of trailer )
Trailer all-up weight 430-pounds ( 195.45 kg )
Trailer tire load per wheel 185-pounds ( 84 kg )[ 24.67 % of Max ]
Fuel Economy:
Outbound - 27.685 mpg
Inbound - 30.274 mpg
--------------------------
Trip Ave. - 28.919 mpg @ 100 km/h
Remarks:
Trailer pulled great.My greatest concern was the wheel bearings.They were not a problem.Handling/stability/tracking all fine.
Bow shock waves from over-taking 18-wheelers created a "push",as I experience anyway.No pitching.No yawing.No cyclic effects at all.
I made a number of excursions up to 70-mph.The rig accelerates like a rocket ship.70-mph is effortless.

Considerations:
From the vehicle logbook of 309,000 mile database,the T-100 experiences a seasonal mpg variation of 8.917% with highest mpg recorded in August,lowest in January.
If one throws this factor into the mix,then it might be possible to realize 31.497 mpg in the Summer for this same run,all else being equal.
If you apply the "gap" factor( Hucho: chapters 4,7,and 8,also NACA Clark-Y slotted-wing drag table ) another 10 % mpg may be possible with the gap-fillers ( as yet not realized with the project ).
If an additional 10 % were realized,then we're talking on the order of 34.647 mpg,at 100-km/h and 4,620-GVW during summer operation.
From the T-100 database,and due to the linear relationship between velocity and MPG,the table for the T-100,at 100 km/h predicts 34.5 mpg in warmer weather.

Parting Thought: If the T-100/Viking combination can indeed achieve 34.5/34.6 mpg,then it would be energy-neutral,or,could be pulled at no gain,nor expense to mpg.
As a telescoping travel trailer,or pull-behind EV Range-Extender with batteries or generator or both ( hybrid ) the full boat tail design might offer greater flexibility to what is presently only limited range vehicles.

As the trailer isn't "finished",and there remains additional drag reduction potential,as well as weight savings,the crazy thing,if ever completed,may yield yet even more interesting numbers.
I've devoted the last seven months to the project,and it's been damaged enough in it's first seven hours of operation that I don't consider it road worthy until I can repair it.
I need to devote time to other activities,and so I have no idea when she'll see road duty again.And as she remains in-complete,she remains an unknown quantity.
I isolated 42 separate vehicles in the T-100/Viking weight class.Everyone achieves lower mpg than the truck/trailer combo.

[MetroMPG]

Phil: giant bummer about that wheel!

But glad to hear you got some data before it went south. The concept of an energy neutral trailer is tantalizing.

At least it gave you some "appetizer results" that will keep the idea simmering on the back burner until you can come back to it.

[aerohead]

Originally Posted by BamZipPow

Nice...

What...no moon caps fer the wheels?

I had intended to have them along with eight other components which didn't happen either.
My early resolution is to make no plans,make no commitments,allow no deadlines to dictate when I "complete" or "road test" a creation.
And not to sound like Polyanna, but if I can ever get all the components integrated into the thing,I may achieve over-unity,getting better mpg with the trailer than without.
I think Mythbusters got 16-mpg at 55-mph with their pair of F-150s.
Getting close to 29-mpg,while pulling a trailer in winter temps at 63-mph doesn't disappoint me,especially with a 1,000-pound weight penalty compared to the stock T-100.
That's also 4-mpg better than this particular T-100 could do on it's best day in the summer when "naked".

[brucey]

I'm really sad to hear that! After all the work you put into it too.
What exactly caused it? Just the lugnuts coming loose?

I might have to take up the slack on a neutral trailer idea.

[aerohead]

Originally Posted by brucey

I'm really sad to hear that! After all the work you put into it too.
What exactly caused it? Just the lugnuts coming loose?

I might have to take up the slack on a neutral trailer idea.

brucey,I think it was basically chronic fatigue and worrying more about respecting others vacation schedules and deadlines,than "finishing" the project and insisting that I do some sort of "shakedown" run before departure.
When the new wheels went on,I was probably thinking that they might have to come back off for some other procedure.The lug bolts never got torqued.
Since the wheels were spin-balanced they might have held on as long as they did, do to the minimum of vibration.
Lucky for me that it came apart at 63-mph rather than the 80-mph I'd intended for the next day.I'd made a number of excursions up 70-mph on the way to Odessa and she went like a rocket.
I would like at some point,to pull the rig across El Mirage Dry Lake at one of the California Timing Assoc. events leading up to Speed Week at Bonneville.
I believe the trailer will allow the truck to achieve 138-mph and 34.6 mpg during warmer weather.
This would mean that the truck would get better mpg WITH the trailer,than without.There is an extreme amount of good science to support the notion.
As I've mentioned elsewhere,pulling the trailer in winter temps(for Texas),and at 63-mph,I'm getting about 13-mpg better than Mythbuster's pair of F-150s running bone-stock at 55-mph.I'm okay with that.