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Old 12-30-2009, 04:31 PM   #66 (permalink)
aerohead
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1st/Final Trip Report ( Crash-Boom!!!!!!!!!!!!!!!!!)

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.
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