Fastest on dirt?

[bbarn]

Tauruck is correct, the front wheels are billet aluminum profiled to our initial design spec. The weight on the front wheels is relatively minor, it is the surface and the wheel profile that make the marks so prominent. On salt, they leave little if any mark, here on the hard crumbly surface, it displaces the playa and leaves ridges on the wheel edges.

We have talked about doing a new set of wheels with a flatter profile on the tread to reduce this. I was very surprised at how responsive the steering is. I think switching it to a flatter profile will not hurt this in any way. In fact, taking some of the responsiveness out of the steering may be a good thing.

For a triangular arrangement, the car handled better than I anticipated. If you look at the internal view of my 200mph pass, you can see that I used little input to move from the left side of the previous run over to the right and back to the left. When I ran over the previous tracks I could tell in the car as it wanted to track in the existing grooves. It did not influence the steering wheel or upset the balance of the car but I knew exactly when I had crossed over centerline. Reducing the radius on the profile should quiet that input down and reduce the marks on the hard surfaced playa.

Controlled dust - Yep, when you look out the back views in either the low or high speed passes, the dust is almost identical. I would have expected a 200MPH pass to eject 'x' amount of cloud and a 360MPH pass to multiply that exponentially. I was shocked that in both passes the amount, volume, height, distance, lingering...all indicators seem to be about the same.

You can look at the rear camera on both passes and see that there is more energy in the area under each flap, but the resulting dust is almost the same. Studying those camera angles, it looks as though most of the dust came from behind the front and rear wheels, the area under the wing is relatively clear.

I had initially thought that it was the exhaust gasses that were keeping this area clear, but then remember calculating the exit speed of the exhaust at roughly 200MPH at WOT. I believe that the three distinct ropes of dust are the results of the air remaining highly laminar at the fuselage as well as the wheel fairing. This supports our initial studies and selection of the NACA66 airfoil characteristics.

[bbarn]

BTW, in terms of stability... On the day of my 200MPH pass, the wind was dead calm. My pass was super stable and extremely uneventful. The car tracked perfectly and moved where I steered it to with no effort.

On Rob's 360MPH pass he had a quartering wind out of the SSE at 15mph gusting to 25. You look at those two passes and see if you can tell that from the videos. The only indicators I can find is the sound of the wind in the microphones. Both drivers reported smooth and stable tracking.

We purposely made decisions in the design phase to limit cross-wind influences and that appears to have worked out brilliantly.

[gearheadeh]

Tauruck is correct, the front wheels are billet aluminum profiled to our initial design spec. The weight on the front wheels is relatively minor, it is the surface and the wheel profile that make the marks so prominent. On salt, they leave little if any mark, here on the hard crumbly surface, it displaces the playa and leaves ridges on the wheel edges.

We have talked about doing a new set of wheels with a flatter profile on the tread to reduce this. I was very surprised at how responsive the steering is. I think switching it to a flatter profile will not hurt this in any way. In fact, taking some of the responsiveness out of the steering may be a good thing.

For a triangular arrangement, the car handled better than I anticipated. If you look at the internal view of my 200mph pass, you can see that I used little input to move from the left side of the previous run over to the right and back to the left. When I ran over the previous tracks I could tell in the car as it wanted to track in the existing grooves. It did not influence the steering wheel or upset the balance of the car but I knew exactly when I had crossed over centerline. Reducing the radius on the profile should quiet that input down and reduce the marks on the hard surfaced playa.

You guys have done an incredible job of this build, I wish you all the success that this car should be capable of in the future.....
Just wanted to say that in my limited experience I would have thought that having a flatter profile instead of the curved one you have-- would do the exact opposite of what you are expecting it to do!

[manta22]

Thanks, Mike. I didn't think there could be that much weight/downforce difference.

Regards, Neil  Tucson, AZ

[robfrey]

Marks were same whether we were moving slow or fast.

[tallguy]

bbarn, thank you for your postings/information.  If it's not too problematic, would
you like to share information about the location or name of this dry lakebed where
your team recently went so fast?  I am impressed with the speeds achieved, although
I never doubted that the car is capable of much  higher speeds (say, 500 mph?).

For many years, I've been observing the friendliness and helpfulness of LSR folks.  It
may be this way partly because there are no cash prizes for which to compete.

In view of the questionable future of Bonneville as a venue, interested minds would like
to be exploring other places (such as Black Rock, Alvord, Hakskeen, etc.) for really fast
vehicles that can't get near their capabilities at smaller venues such as El Mirage or any
paved airport runways.

Best of luck to you and Rob, and the rest of the Carbiliner team.

[tauruck]

That all looked great and I think you guys hit the nail on the head.
I'm all ears for wheel spin and expected more than one tiny lift (I think I heard).

Awesome job and with so little dust I'd say you found the perfect track.
The surface I'll be running on is similar and you've lifted a big weight of my shoulders.

Great driving skills guys. I'm proud to know you.

[SPARKY]

Minimal dust has a lot to do with the shape of the car as well as the racing surface I think!

Blue   

[manta22]

Marks were same whether we were moving slow or fast.

That eliminated the downforce possibility but your explanation of the wheel profile explains all.

Regards, Neil  Tucson, AZ

[Peter Jack]

If I'd discovered a place where I could test that sort of vehicle without having to worry about recreational traffic I'd be very reluctant to let anyone know where it is. I think these guys have been more than generous with the information they have given out.

Congratulations to Rob, Brandon and the team on their successes. I can only hope that Bonneville is restored to the point where they go out and show the world what they're capable of accomplishing.

Congratulations also go to Blue. That has to be the cleanest dust trail I've ever seen which would indicate, I think, that the aerodynamics are pretty close to spot on.

Way to go guys!!!  

Pete

[bbarn]

I think the location will come out in due time. Here are some things I can share that will keep the mystery from eating everyone up...

We have been referring to this place as Area 52 since there isn't a name we could find associated with it.  

First, dust is a massive issue. We abandoned the first 1.2 miles of track to avoid some very loose dirt. Has a lot to do with weather, flooding, drying cycle and time. I have talked to several of the "Big Boys" as they have asked for more details on location as well. If you don't have dust controls in place forget this location.

We actually made a short run then spent the rest of the first day trying to eliminate dust from filling the cockpit. Several steps were taken - Get out of the loose stuff at the beginning, increase the holes in the windscreen to create more pressurization and add more sealing to the cockpit.

Second, location, location, location...There are NO services in the basin we used. Closest thing to civilization is 30 miles down a dirt MOUNTAIN road. Switchbacks, off camber, 150 foot drop-off with no guide rails....locals told us if it rains just stay put, the road is impassable until it dries.

If you are not nimble in your logistics, getting there will be treacherous at best - deadly at worst. No kidding it is a 30 mile jaunt up a 20 ft wide dirt road. (the 10 feet left and right of the center-line of the road are soft so be careful   ) Then you turn onto the playa via two wheeled "path" 90 degrees to the direction of travel. This has a berm/curb that you have to negotiate over or around. Since the entry is 90degrees and the path is only wheel width wide, a large or long trailer will struggle here.

Surface - We don't have enough data about surface characteristics yet to make much of a determination on the long-term viability of the location or the support of multiple vehicles on the surface. We were there once and we know they had torrential flooding in June. We made some local contacts and asked questions about how the surface was when we were there vs other times of the year.

We did some mapping of the surface with GPS while we were there and looked at where we may be able lay out multiple tracks or alternate tracks. Nothing definitive yet, but certainly something to consider.

Surface observations: Our track surface held up well, although we only made a handful of passes and several of them were "fresh tracks". We did run support vehicles up and down the track several extra times and it seemed to hold up well. Not sure that multiple high-power passes would result in the same scenario.

Location - This place is remote! There are NO facilities anywhere close, it is 30miles just to get to a hard surface road. Holding a meet here would involve Permits, paperwork and some logistical planning on a massive scale. I actually had a convo about airlift capabilities to get onto the surface. For some, this may be the only option on or off the surface.

Stay tuned, I think more will be revealed once we get more details. As for a Bonneville Replacement/multi-car meet location - Won't happen unless someone has a bunch of tunneling equipment to provide better access and lots of money to put up some kind of a facility.

This must be what our LSR counterparts in Australia put up with to get to their salt only more mountainous. We have a shorter trip, but the road is less passable I think.

[ack]

bbarn, thank you for your postings/information.  If it's not too problematic, would
you like to share information about the location or name of this dry lakebed where
your team recently went so fast?  I am impressed with the speeds achieved, although
I never doubted that the car is capable of much  higher speeds (say, 500 mph?).

For many years, I've been observing the friendliness and helpfulness of LSR folks.  It
may be this way partly because there are no cash prizes for which to compete.

In view of the questionable future of Bonneville as a venue, interested minds would like
to be exploring other places (such as Black Rock, Alvord, Hakskeen, etc.) for really fast
vehicles that can't get near their capabilities at smaller venues such as El Mirage or any
paved airport runways.

Best of luck to you and Rob, and the rest of the Carbiliner team.

I posted a about 10 years ago it still may have some useful information

Breedlove told us about the Alvord Desert when we starting the streamliner in late 2002.  He had been there and told us the surface was good but not long enough for him.  I flew up there on Thanksgiving weekend 2002.  At that time the surface condition was very good and much different from Black Rock it had a hard white alkali looking surface and no dust.  It looked like there was about 6-8 miles usable. The southern end was wet at that time.  There was only one family there.  They we from northern Oregon and were riding ATV and Motorcycles. They told us that there was almost never anyone there and conditions could range from wet to dry and dusty.

The thing I have found with all the dry lakes in northern Nevada is the conditions can change fairly rapidly depending on the weather conditions and season.  I have ridden off road bikes on most of the dry lakes north and east of Black Rock Desert and there are many of them ranging in size from 1 -15 miles long.  Once we camped on the west side of Black Rock and rode east across the lake that was dry and dusty except for the Quinn river that had some water in it.  We continued cross country over the Jackson Mountains for about 35 miles east and then came back. A rain storm had passed by and when we tried to cross Black Rock three hours later we were in mud at least 12 -18 inched deep at the eastern edge.

Another time one of my tenants that was building a Cadillac powered twin engine streamliner was looking for a place to test.  He had tried Black Rock and just dug in when he tried to run, He had heard about a dry lake about 30 miles north west of Lovelock NV I think it is called Blue Wing Flats.  I flew him up and the surface was great similar to Black Rock but much harder and no dust. I remembered riding across it on my motorcycle previously and it was dusty at that time.  He loaded up the streamliner and left about a week later.  I flew up and met him there.  The conditions had completely changed it was hard enough to run on but so dusty that he could not see because of the dust getting into the cockpit.  Made one run and went home.

I don’t know what would be the right time for the Alvord and running an event there would be a crap shoot but it could be good if conditions were right. It’s a very remote location so you would need to bring everything you could possibly need.  The people we met on the Alvord said there is a gas station and I believe they said a small store just up the highway but we didn’t check it out. Denio Nevada is about 70 miles south and has food lodging and gas.

As for running on FAA airstrips it just depends on who’s running it. We did some testing in Nevada and we had the choice of several air fields.  The one we used was just repaved 75 feet wide by 7500 feet long courtesy of the FAA. The Taxiway was brand new 50 X 7500 feet.  All most all of these rural airstrips are run by private operators that receive funds by the FAA and they have pretty much total control of the airport.  We spent all day there three times and never had a single aircraft land or take off.  We monitor the radio in case some one wants to use the airstrip.  Unfortunately this airfield has been taken over by a freight carrier for hub operation in the area and is no longer available to us.  There are a number of other locations though available in Nevada.       

[Jack Gifford]

I'm on the wrong coast to know about playas, etc., but I had noticed Searles dry lake on a map of California. It's about 12 x 8 miles, and appears quite level, smooth, and flat in the couple pictures I found. Lots of mineral mining there, so possibly it's prone to Bonneville-type problems. Also, apparently not easily accessible. Anybody know more about it?

[It's the origin of the "20 mule team" to haul Boron to a port]

[Bret Kepner]

Pretty much every available inch of Searles has been destroyed by mining.

[fredvance]

Imagine that!!