TerraLiner:12 m Globally Mobile Beach House/Class-A Crossover w 6x6 Hybrid Drivetrain

[biotect]

************************

2. Tatra Off-Road Firetruck


Next, I came across a cool website about “wildland fires” in the Great Basin, Nevada, at http://www.angelfire.com/nv/blm/page1.html .

To help control fires they've used Unimogs – see http://www.angelfire.com/nv/blm/pics.html , http://www.angelfire.com/nv/blm/engines.html , and http://www.angelfire.com/nv/blm/unimog.html . But about a decade ago they acquired a specially converted Tatra, made by the American Truck Company (ATC) – see http://www.angelfire.com/nv/blm/ATC.html , http://www.thebigredguide.com/fire-...n/sands-fire-apparatus-wildland-ultra-xt.html , and http://www.fireapparatusmagazine.co...t-uses-proven-czech-off-road-engineering.html .

Here are two videos:


[video=youtube;v-f4P7mrGIk]http://www.youtube.com/watch?v=v-f4P7mrGIk#t=159 [/video]


The first video describes the research and procurement process, and has commentary by a Tatra technician, who emphasizes the torsion-free nature of the Tatra backbone-tube frame. The truck's automatic transmission had to be actually incorporated into the backbone tube, and if I'm hearing the video correctly, "Twin Disc" was subcontracted to do this, and has also done the same for Tatra trucks sold to India -- see http://en.wikipedia.org/wiki/Twin_Disc , http://www.twindisc.com , http://www.twindisc.com/en/industrial/industrial-products/power-shift-transmissions , http://twindisc.qmworks.com/data/en...ds/Automatic_Transmission_System_Brochure.pdf , http://twindisc.qmworks.com/data/en...ontrol/media/downloads/Auto_Transmissions.pdf , http://www.tatratrucks.com/trucks/product-catalog/t-815-7/ , http://www.tatratrucks.com/why-tatra/tatra-vehicle-design/tatra-transmissions/ , and http://www.twindisc.com/search/?zoom_query=tatra .

In 2003 ATC built 6 of these vehicles on a 815 chassis, for the US Bureau of Land Management – see http://www.trucksplanet.com/catalog/model.php?id=1855 :







But just the following photograph alone seems to suggest that more than 6 were built:





Sure, these are not RV conversions, but this is another example of how a certain vehicle type -- namely, large off-road fire truck -- demands a torsion-free, stiff frame.


************************

 

[biotect]

************************

3. Tatra Off-Road Motorhome


The following is the only Tatra-based expedition motorhome that I've been able to find on the web, so far – see http://www.theoverlander.org/my-wheels/trucks/tatra-815-2-6x6-expedition-truck.html .

If anyone comes across others, and would like to post them here, that would be great! See for instance the list at http://www.theoverlander.org/my-wheels/trucks/ , http://www.theoverlander.org/my-wheels/trucks/Page-2.html , and http://www.theoverlander.org/my-wheels/trucks/Page-3.html . The usual suspects, Unimog, MAN, Iveco; some local color with Leyland; and just one Tatra….. .

The camper was fabricated by a UK company called “Overland Vehicles” – see http://www.overland-vehicles.co.uk :













The short article that the owner wrote makes for very interesting reading, because it directly speaks to the "ethics of size debate" that seems to constantly come up, whenever people consider larger motorhomes:


................................With a family of 5 on the road for two years we did struggle with the perpetual compromise of size: big and comfortable but less agile, heavy and difficult to blend in!
................................Smaller and lighter is more subtle and maneuverable but means less space and comfort! No clear winner, but we wanted as much space and comfort as possible with
................................permanent bed areas to ensure we could continue for as long as possible. We wanted a a big body (7m) and a crew cab. This meant we needed the length of a 6 wheeler.

................................We looked at M.A.N.s and Mercedes but affordable 6X6 crew cabs variants are virtually non existent in the UK and pretty rare in Europe. Those we found seemed to be
................................asking a high price for them too. We looked at military vehicles as they often have crew cabs and came across Tatras. After being seduced by their 8X8 trucks plowing
................................through pretty much anything we made contact with Malcolm Douglas - a UK Tatra expert and ex Dakar Truck racer. He introduced us to Dealers in Czech and we found
................................one in January 2011. – see http://www.theoverlander.org/my-wheels/trucks/tatra-815-2-6x6-expedition-truck.html .


Interesting, then, that although this vehicle is based on a Tatra 815-2 6x6 chassis, it still follows the standard format of the large expedition motorhome, with cab separate from camper. I wonder if this was mechanically necessary, or whether it simply had not occurred to the owner that a Tatra chassis might be stiff enough to support a more fully integrated design? The vehicle was originally a construction truck, so even though it's designated “815”, perhaps it's not as stiff as the military version?

All best wishes,



Biotect

 

[egn]

As we intend to spend a fair amount of time in the east direction from Europe, a Kamaz 6x6 was also on the short list. I liked it very much for its simple technology and its good off-road performance. I was just a few weeks away of purchasing one, but had serious problems to organise the import into EU. So I dropped the idea and looked for something different.

I never thought about a new modern MAN or Mercedes truck, as this was to much electronics and also didn't fit our budget. We looked also for a used Action Mobil and Unicat. But the cabin of the Action Mobil KAT 6x6 didn't match our requirements for long-term travel, and the Unicat MAN 6x6 was much to expensive.

As I knew the KAT from my time as in the german army in 1979 for its high capabilities - we did just crazy things with 8x8s at this time - I looked for a used 6x6 and finally found one, in best condition and bought it immediately. It then took about 4 weeks to write a specification and find a builder who was willing to build that what we wanted for a reasonable price. This was the birth of Blue Thunder and about 18 months later we had our first voyage to Russia. :wings:

 

[egn]

It's based on a Tatra 815-2 6x6 chassis, but for whatever reason, follows the standard format of the large expedition motorhome, with cab separate from camper. I wonder if this was mechanically necessary, or whether had not occurred to them that a Tatra chassis might be stiff enough to support an integrated design? The vehicle was originally a construction truck, so even though it's designated “815”, perhaps it's not as stiff as the military version?

I think the answer is simple:
It just costs a lot more money to build an integrated design.
An empty box costs empty about 10.000 € - 30.000 €, what do you think would a integrated cabin would cost?
And who would take the risk for such a complete new and unproved concept?

 

[biotect]

Yes, that must be it.

A completely new and unproved concept that has not yet been explored even by young, penniless MFA students in transportation design programs, who have nothing to lose and everything to gain, because the concept will probably only stay a "paper" exercise.....:sombrero:

BTW, over the next year or so, if you ever come across anything even remotely like this, even if explored only at the conceptual level, please warn me. Half the potential impact of this thesis project is that it just might be "completely new", as you suggest. I am not certain that it is, but it might be. I've scoured the net collecting every "mobile home concept design" that I could find, and I've still not come across anything remotely similar. But who knows, my design competition could be out there, drawing and scribbling away as I write these words.....

************************************


For what it's worth, I only found it perplexing that the owner of the Tatra expedition RV above did not explore a more integrated design, because in his short article he makes it clear that space was a big issue for him and his family. He's a young married guy with 3 small children, and so his expedition RV is not a retirement motorhome. Again, in his short article he writes:


................................With a family of 5 on the road for two years we did struggle with the perpetual compromise of size: big and comfortable but less agile, heavy and difficult to blend in!
................................Smaller and lighter is more subtle and maneuverable but means less space and comfort! No clear winner, but we wanted as much space and comfort as possible with
................................permanent bed areas to ensure we could continue for as long as possible. We wanted a a big body (7m) and a crew cab. This meant we needed the length of a 6 wheeler......

................................One problem with a truck this big is that we won't be able to get close to the action, i.e. may have to stay outside small villages and roads.

................................– see http://www.theoverlander.org/my-wheels/trucks/tatra-815-2-6x6-expedition-truck.html .


I get the feeling that some on ExPo simply assume that most people will use their expedition RV's exclusively as couples. And because the spatial needs of two people are finite, they reason that larger motorhomes are sociologically, economically, politically, and morally unjustifiable. Again, see the “Ethics of Third World Travel by Motorhome” thread, where people with very different views in response to the "ethics of size debate" continue to passionately trade opinions….. It's at http://www.expeditionportal.com/for...ld-Travel-by-Motorhome/page6?highlight=ethics . Kind of nice, that thread, because it continues to grow, and I don't have to do anything! :ylsmoke:

So egn, you also strike me as a family man, and perhaps that's why the theoretical potential of a more integrated design for a large, expedition-class RV interests you?

Some seem to assume that such a large vehicle is the kind of toy that only ultra-rich people who have more dollars than sense would want to buy. But the mere existence of a large market for German “Liner”-class motorhomes, or the large market for American class-A motorhomes, suggests otherwise. No doubt there are lots of successful professionals and owners of small businesses who are very committed to their families, but who also love travelling and camping in the middle of nowhere, with the same.......



And for a family of 5, bigger is most definitely better, even if it does often mean parking outside small villages that have narrow roads. This owner's short article speaks to such issues in a, direct, personal way.

All best wishes,


Biotect

 

[biotect]

egn,

Great images of blue-thunder showing off her muscle in Russia! And thanks for the background behind her genesis; she's a beautiful machine.

No doubt you already know this: a few months ago Kamaz won Dakar 2014 for trucks – http://rbth.com/sport/2014/01/21/kamaz_celebrates_victory_in_dakar_2014_33401.html , http://rbth.com/photo_of_the_day/20...celebrates_its_win_in_dakar-2014_r_33365.html , http://voiceofrussia.com/news/2014_...ster-s-Karginov-wins-rally-among-trucks-7195/ , http://www.dakar.com/dakar/2014/us/stage-13/rankings/overall-trucks.html#ancre , http://www.redbull.com/en/motorspor...27287159/dakar-2014-stages-photos-news-so-far , http://www.redbull.com/en/motorsports/offroad/stories/1331624452783/daily-dakar-diary-stage-thirteen , http://www.redbull.com/en/motorsports/offroad/stories/1331624452158/daily-dakar-diary-stage-eleven , http://www.redbull.com/en/motorsports/offroad/stories/1331628512013/toughest-dakar-rally , http://www.redbull.com/uk/en/motorsports/offroad/video-series/1331580335186/dakar-2013-videos , and http://www.dakar.com/dakar/2014/us/summary/videos-galery.html .

What's more, the Dutchman just passed a flipped car, whereas Karginov stopped to help the driver, and lost 9 minutes. The judges gave Karginov his nine minutes back, and he won the race!

Nice guys finish first.


[video=dailymotion;x19x135]http://www.dailymotion.com/video/x19x135_us-stage-12-13-truck-quad-stage-summary-la-serena-valparaiso_auto?start=23[/video]

[video=dailymotion;x19ysdy]http://www.dailymotion.com/video/x19ysdy_us-best-of-truck-dakar-2014_auto?start=164 [/video]



It's great watching these big blue Russian trucks passing cars, motorbikes, and quads....:rally_guys:


And this gives me a good excuse to post a few pics of what appears to be a Russian Kamaz troop carrier, broadly similar in appearance to the Drehtainer MFD:





See – http://englishrussia.com/2012/02/17/kamaz-releases-its-2000000th-truck/2/ .


Perhaps mounting an integrated cab/body on top of a 6x6 or an 8x8 is not so new after all, if only because the world's various militaries have been doing it for decades.

All best wishes,


Biotect

 

[charlieaarons]

Yes, with 12-16mm steel armor plate that weighs how much??

Charlie

 

[biotect]

Yes, with 12-16mm steel armor plate that weighs how much??

Charlie

In some places a bit of armor might come in handy......

But concealed, non-visible/embedded armor is best – see http://www.texasarmoring.com :




***************************************

Seriously though, see http://www.dhushara.com/book/explod/mine/mine.htm , http://2009.igem.org/Team:Edinburgh/projectmain/landmines , http://www.viewsoftheworld.net/?p=1967 and http://newsoutofafrica.wordpress.com/2008/04/05/miss-landmine-angola-2008/ , http://landminesinafrica.wordpress.com , and https://landminesinafrica.wordpress.com/tag/south-sudan/ :






Sure, these maps do not positively recommend armoring, but they give one pause for thought, especially given that many overlanders are inclined to venture far off the beaten path, in remote areas where mines may not have been cleared up.

Just wondering: what is the annual. worldwide frequency of overland and expedition vehicles getting blown up by land-mines?

Maps of old mine-fields help, but apparently in most years at least one overland trip in North Africa sets off a land-mine somewhere -- see http://www.sahara-overland.com/mines/ , and also see http://www.iranhumanrights.org/2014/03/landmine-explosion/ .



***************************************

egn: your MAN KAT “Blue Thunder” is ex-military. Did it come equipped with armor? Is the armor still on?

.

 

[biotect]

*************************************


Tatra 6x6 versus Zetros 6x6 Chassis Weight:

Some Surprising Comparative Data


*************************************


Just a bit more about the Tatra-based expedition Motorhome, discussed on page 8 of this thread:






Again, see http://www.theoverlander.org/my-wheels/trucks/tatra-815-2-6x6-expedition-truck.html for the owner's short description.

Because the vehicle is based on a Tatra 815-2 6x6 “tipper”, one might think that the underlying chassis should be much heavier than most comparable vehicles. If only because Tatra uses a unique backbone-tube drive system, with independently swinging half-axles, providing a very stiff and torsion-free mounting frame – see http://www.tatratrucks.com/why-tatra/ , http://www.tatratrucks.com/why-tatra/tatra-vehicle-design/ and http://www.tatratrucks.com/why-tatra/tatra-vehicle-design/tatra-vehicle-design-1/ . egn, in a post in “pivoting frames and mounting campers,” you seemed to indicate that this system might result in greater comparable weight for the Tatra?

However, according to one brochure, the base chassis of the current Tatra 6x6 "tipper" might actually be lighter than a comparable Zetros 6x6....... :yikes:. According to one brochure, the Tatra Phoenix 6x6 weighs 9,800 kg, whereas the Zetros 6x6 weighs 10,500 kg:



For the Tatra Phoenix 6x6, see http://www.tatratrucks.com/underwood/download/files/tatra-phoenix-product-data_en.pdf , http://www.tatratrucks.com/trucks/customer-segment-catalog/construction/ , http://www.offroadtrucks.com.au/models/6x6/ , http://www.tatratrucks.com/underwood/download/files/tatra_terrno1_en.pdf , and http://www.tatratrucks.com/trucks/c...struction/more-trucks/6x6-three-way-tipper-1/ ; and for the Zetros 6x6, see http://www.unimogcanada.com/zetros.pdf , http://www.mercedes-benz.dk/applications/brochure/trucks/Fld_Zetros_Construction_en.pdf , http://www.tradingeurope.at/Downloads/Zetros_engl.pdf , and http://www.mercedes-benz-media.co.uk/doc/2124/zetrostechnicaldata.pdf .

However, granted, the fine print in the Tatra brochure states, “Standard chassis version for mounting the body/superstructure: shortest wheelbase, front axle suspension (8 tons) and light-duty combined rear axle suspension.”

The data provided by Tatra product brochures on the Australian website are probably more realistic – see http://www.offroadtrucks.com.au/models/6x6/ . There, the kerb weight of the Tatra Phoenix 6x6 with tipper body, is 12,620 kg – see http://www.offroadtrucks.com.au/wp-content/uploads/2013/07/6x6-Phoenix-Tipper1.pdf . But this still compares favorably to the Zetros 6x6, because 10,500 kg is the “bare chassis” weight of the Zetros 6x6, i.e. without tipper body. The Australian Tatra website seems to place the “bare chassis” weight of a Phoenix 6x6 at either 11,100 kg or 11,900 kg – see http://www.offroadtrucks.com.au/wp-content/uploads/2013/07/6x6-LWB1.pdf and http://www.offroadtrucks.com.au/wp-content/uploads/2013/07/6x6-ROPS-Rear-Steer1.pdf .

This seems remarkable, because the Tatra frame is much stiffer and therefore, presumably, should be much heavier than the Zetros?

grizzlyj, you have been advocating for the presumably much lighter, flexible frame of either a Mog or a Zetros, so what do you make of this comparative data? It would seem that a Zetros 6x6 is not that much lighter than a comparable Tatra after all, even though the Zetros frame twists, and the Tatra's ultra-stiff, torsion-free backbone tube does not.

I am probably missing some critical piece of information here, but the comparable kerb weights of the Zetros 6x6 and Tatra 6x6 seem awfully close....

All best wishes,



Biotect

 

[grizzlyj]

I'm surprised the weights appear close, but the Tatra weight above doesn't say which wheelbase that applies to, if that's just for the backbone then possibly you would add comparatively more weight mounting a rear flat bed, and the Zetros already comes on the wheel and tyre combo you would need to add to your Tatra which are not light. And in any case the Tatra is much worse due to its lack of flex so should not be further discussed

Not exactly on topic but for comfort the closer to the centre of rotation you sit (so midway between the axles on any two axle vehicle) the better. MAN KAT and Tatra would be expected to be worse than a Zetros form looking at that aspect alone, but the independent suspension design may well more than compensate for that. Zetros and Unimogs have identical doors incorporating the curve of the front wheelarch, so driver poition in relation to the front axle between these would have to be similar.

 

[biotect]

Hi grizzlyj,

Very much agree with you about the driving position in the Zetros, which is why I was so happy to see Tatra "chassis-only" products with CBE designs. But it seems that egn does not --:sombrero:

I'll be posting shortly on the sub-theme of engine placement, and we'll see how egn responds to the arguments.....:REOutArchery02:

Just wanted to finish chassis considerations first, so that this reads like a "cluster" for any new people who might join the thread in future.......


*********************************

Tatra Chassis-Only Products

*********************************


Again, see the comprehensive Tatra military catalog at http://www.tatratrucks.com/underwood/download/files/tatra-military-vehicles_en-2.pdf . Tatra seems quite happy to sell just a chassis without a cab.

Furthermore, in its 4x4 and 6x6 variants of the 815-7 "chassis-only" product offering, Tatra provides no less than three (!!) different engine placements:

1. CF, or “cab forward”, i.e. cab in front of the engine

2. CBE, i.e. cab behind the engine

and even, it seems.....

3. CAE, or cab-aside/beside-engine.

Pages 28 – 35 of the comprehensive military catalog describe these "chassis only" variants, and also see the independent brochures at http://www.tatratrucks.com/underwood/download/files/tatra-t815-790r99-8x8-chassis_en.pdf and http://www.tatratrucks.com/underwood/download/files/tatra-t815-790rk9-6x6-chassis_en.pdf :





So a fully integrated expedition motorhome mounted on a Tatra chassis could, indeed, be CBE, just like the Zetros.

All best wishes,


Biotect

 

[biotect]

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No Pivoting Sub-Frame?

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Here are some more photos of the Tatra expedition motorhome conversion, this time of the construction of the camper. The owner writes in his short description:

.....................................……we have gone for a mix of insulted steel frame for strength and repairability but with an internal layer of GRP honeycomb for
.....................................insulation without cold bridges. A total thickness of about 50mm should see us well insulated.

.....................................- http://www.theoverlander.org/my-wheels/trucks/tatra-815-2-6x6-expedition-truck.html


Looking at the photos of the build, I then started wondering: Where is the 3 or 4-point pivoting sub-frame?







As near as I can tell, there doesn't seem to be any.

This may well be that truly rare beast, a very large expedition motorhome that gets along perfectly well without a sub-frame, because the ultra-rigid Tatra backbone tube, combined with swinging half-axles, takes care of everything.

All best wishes,


Biotect

 

[unirover]

A lot of this thread is interesting in theory, but on a practical level the bigger 6x6 and 8x8 vehicles are just too big to use in true real world expedition conditions. The MaxiMog and the Kiravan are both examples of theoretically awesome vehicles that can't really go anywhere in practice due to size and weight. They are a great exercise in what a lot of money and great imagination can make but they are totally divorced from reality. Unicat (and the others) are happy to build you a totally incapable vehicle if that is what you want and you have the money.

While the MAN KAT and Tatra's are very capable for their size, they are non-the-less huge and heavy. Narrow bridges and roads, low overpasses, and roads/bridges that can't support much weight (most of the 3rd world) are going to stop larger vehicles from going very far off the beaten path. Basically you are limited to roads used by commercial vehicles which can be pretty extreme in places like Russia or Mongolia but you can't go much beyond that.

A 8x8 MAN KAT literally has a small army of support vehicles. They don't go anywhere solo in the army because if you get it seriously stuck (not that hard to do on soft ground or even in wet grass) then you are stuffed. All the great suspension travel and chassis design does little good when you are mired up to the axles in sticky mud. When your truck weights more than 15 tons the odds or finding a handy tree strong enough to pull out from are pretty slim.

Back when overland companies used to do London to Cape Town tours, the consensus with overland drivers was that anything bigger than a 5 ton 4x4 truck was too big and they had a strong financial incentive to go as big as possible. The Bedford MK, Mercedes 911, Unimog U1300L was considered the ideal size although they did occasionally go with bigger vehicles.

Some of the vehicles pictured on this thread are just too big to be of any practical use. There are good reasons why the Panthers are only used on paved runways big enough to land a 747. Some of the 6x6 could be useful if you really need a bigger vehicle but the 8x8's are pointless IMHO. Don't get me wrong, I love big MAN's, Zetros, Tatras and find this thread interesting, but as an overland/expedition vehicle, the actual physical size and weight are going to be your limiting factor, not the suspension design, body design or where the engine/cab is located.

Some of those vehicles are so big you can't even drive them on-road let alone off-road. The Action Mobil 8x8 needs special permission on some roads in Europe. Anything higher than 14' feet in the USA risks hitting low bridges even on major highways. A lot of smaller remote roads are limited to 10 or 15 tons. You can't turn them around on smaller roads and most campgrounds can't take them. Forget about going into cites or small villages. You can forget about small bridges, ferries, national parks, and overgrown tracks. In Africa, large vehicles get unloaded into smaller ones when it is time to do go to truly remote areas. Most places you can drive a MAN KAT 8x8 are almost by definition not remote. I know there are exceptions of people taking larger vehicles to remote areas but that is in despite of the vehicles' size not because of it. In the real world, big expedition vehicles struggle where most other off road vehicles have no problems, but of course they have more room. The question is how much do you want to sacrifice in terms of ability for size.

If you need that much room, why not just get two vehicles? Two Unimogs U1300L will go more places than any single 6x6 or 8x8 MAN, Zetros or Tatra could ever dream of going. With two Unimogs, you might even have a chance of pulling a 8x8 truck out of the mud

 

[mog]

unirover
Outstanding post !

 

[grizzlyj]

Two Unimogs U1300L will go more places than any single 6x6 or 8x8 MAN, Zetros or Tatra could ever dream of going. With two Unimogs, you might even have a chance of pulling a 8x8 truck out of the mud

Two Mogs parked up back to back could be zipped together to form Biotect's 8x8 camper too