Part 5: Hans Nibel – Benz and Mercedes Give Rear Engines A Try
Hans Nibel was born in 1880 in Moravia, then part of Austria-Hungary and now in the Czech Republic. After graduating from the Technical University in Munich in 1904, he went to work for the pioneering automobile manufacturer, Benz & Cie. (Company). He was promoted regularly, and by 1911 was an officer and Chief Technical Director, and by 1922, he was a board member. He was of course involved in many of the numerous successful cars by Benz during this time, including the legendary Blitzen Benz, the fastest racer in the world at the time. We’re going to stick with his involvement with rear engine cars, as Benz, and after their merger, Mercedes-Benz, were significant players in what led to the Volkswagen.
Early on, Nibel saw the inherent and far-reaching potential in Rumpler’s Tropfenwagen, and persuaded Benz to buy a license for the manufacturing rights in order to develop new cars based on Rumpler’s principles as well as to build some racing cars on these principles as test beds. The first result was the 1923 Benz Tropfenwagen RH (Rennwagen Heckmotor), in essence the first modern mid-rear engine racing car.
Nibel made a number of detail changes to Rumpler’s rear suspension and transaxle, including the use of inboard brakes. Although under-powered with its 65 hp DOHC six, two of them made a fine showing on their maiden outing at Monza, and they left a deep impression on all who saw them. That included Ferdinand Porsche and Adolf Hitler, who first briefly met at a race in 1925 where they both saw the Benz Tropfenwagen racers.
After Mercedes and Benz merged in 1926, Nibel had to work under Porsche, who was then Mercedes’ Technical Director. Porsche at the time felt that his line of famous supercharged 200 hp SSK/SSKL front engine racers were still inherently superior, and the little Tropfenwagen racers were abandoned.
It makes me wonder if Harry Miller’s brilliant 1926 FWD Indy racer was inspired by the Benz RH, given that its drive train configuration is essentially the same but turned 180 degrees, thereby driving the front wheels. The key benefit was the same in both: no drive shaft, so as to allow the driver to sit much lower and thus reduce aerodynamic drag. In Indy oval racing, FWD was not at all a disadvantage, as traction was not critical due to running starts and constant high speeds.
After Porsche left Mercedes, he took up the concept with a vengeance, and secured funding from Hitler for the series of brilliant and formidable Auto Union GP cars starting with this Type A in 1934. They were the first mid engine racing cars to win repeatedly, and left an even longer lasting impression on the eventual format of all GP racing cars, some twenty years later. Rumpler was the father of an enduring concept, to this day.
Already in 1927, Nibel was given the go-ahead to develop small rear-engine cars. The first was this 120 prototype from 1931. It was advanced all-round, with a central tube frame, independent suspension and an air-cooled flat four engine in back. Although not put into production, this is as much as a progenitor to the actual Volkswagen (or Tatra) as anything, given that in 1931, neither Porsche or Ledwinka had actually built something remotely comparable.
Apparently there were issues with the air cooled four, as the next evolution, the 130 had a 1.3 L water cooled inline four at the rear. That would turn out to be a fateful decision, as an air-cooled boxer four is inherently much lighter and shorter, critical in the case of rear engine. The 130 went into low-volume production in 1934,
We can see that the front suspension used two transverse leaf springs. Ganz was consulting with Benz at this time, so that may reflect his involvement, although others had used it before. The rear swing axles had coil springs. The obvious issue with this and subsequent other rear engine Mercedes were that they were excessively tail heavy due to their long and heavy inline water-cooled cast iron engines. Ride over the poor surfaces common at the time was superior to the conventional smaller Mercedes models, and at the low-moderate speeds of the time, handling was considered adequate. But at the limits it was capable of doing what every excessively tail-heavy swing axle car could do, and that was neither pleasant nor safe.
In the 150H sports car of 1934, Nibel reverted to the mid-rear engine format, essentially an update of the Benz Tropfenwagen racer. It used many 130H chassis components, and its drive train flipped 180 degrees, as well as an enlarged and more powerful SOHC engine. As such, it was the first production mid-engine sports car.
More intriguing was the 150H Coupe, which won several long-distance road races in 1934, and looks more than a bit like a somewhat cut-down Volkswagen.
Mercedes’s final rear engine car was the 170H (“H” for “Heck”, meaning rear), which replaced the 130 in 1936. It was introduced at the same time as the traditional front engine 170V (V for “Vorn” or Front), so as to provide consumers the option of two different formats with the same basic engine.
Unsurprisingly, the traditional 170V trounced the 170H in sales, thanks to a bigger trunk, no tricky handling at the limit, and perhaps most importantly, its traditional large upright Mercedes radiator grille on a long hood in front. Mercedes buyers tended to be conservative. The fact that the 170H was considerably more expensive was the final coffin nail, and the plug was pulled in 1939.
That ended Mercedes’ unhappy experiment with rear engines, although it would yet play a role in the development of the Volkswagen, in part due to its experience in building small numbers of rear engine cars like the 150H.
Part 6: Hans Ledwinka – Innovator or Copycat?
Hans Ledwinka, born in Klosterneuburg, Austria in 1878, played a complicated role in the genetics of the Volkswagen. Ledwinka was a brilliant engineer credited with many innovations, and I have sung his praises here at CC. If the tone of this chapter comes across a bit negative, it’s only because it’s been quite fashionable for some time to attribute more to Ledwinka than is justified on the facts. In particular, it’s all too common to come across claims that the Volkswagen was simply a copy-cat Tatra.
Tatra did go to court over patent infringement by Volkswagen, and eventually won a judgement in their favor well after the war, and VW paid Tatra damages (details further down). This alone, as well as certain obvious visual and technical similarities between the Beetle and the Tatras has been used repeatedly to reinforce that the myth that Porsche essentially ripped off Ledwinka, and used the protection of Hitler to do so.
It’s actually a lot more complicated (or not) than that, and I’m going to focus on primarily those issues here. But for what it’s worth, Ledwinka was no stranger to using others’ ideas and designs too.
We’ll skip over Ledwinka’s early years at Nesselsdorfer, where as an 18 year old he joined Edmund Rumpler in designing some less than stellar early horseless carriages, as well his much more successful S4 and S6 cars of the teens. After a stint with Steyr, Ledwinka returned to Nesselsdorfer to design a light, small, and relatively affordable car, one that would be his first enduring and perhaps his greatest masterpiece, the first to bear the name Tatra, the T11. It was designed between 1921 and 1922, and went into production in 1923.
It was a highly successful and quite advanced synthesis of several existing components: a central tube, that would serve both as the frame of the car as well as enclosing the drive shaft. Affixed rigidly at the rear there was the differential housing, from which emanated the swing axles. And attached equally rigidly at the front of the tube was an air cooled boxer twin, over the solid front axle. The engine’s flywheel had vanes and doubled as the cooling fan, whose output was directed to the cylinders via shrouding.
The central tube as a primary carrying member goes back to the 1908 Rover 8 HP, and the swing axles are of course from his former boss, Edmund Rumpler. But the combination was essentially new, and Ledwinka wasted no time patenting all of it, and more, including variations with the engine at the rear, although that was strictly on paper at the time. But that patent, for a rear engine attached to a transaxle, was also used in legal action against Ganz, no less.
The T11 and its successor, the T12, developed a superb reputation for their ruggedness, economy of operation and capabilities. Eventually, Ledwinka added two more cylinders to create the T30, and its evolution, the 57. These were highly capable cars, and Ledwinka’s extensive experience with air-cooled boxer engines made him the world’s leading expert on them, most critically their cooling systems.
Other air cooled engines back then typically just relied on large fins and the passing air over them at speed, or some sort of primitive blower assist. But Ledwinka had been refining the blower and its ducts for years, and as can be seen on this T57 engine, it looks quite advanced and was well proven. Ledwinka patented several variations on the theme of ducted fan air cooling schemes, so general in their scope that there was essentially no way around them. That would include the Volkswagen.
In 1930, Ledwinka’s son Erich started working at Tatra. Along with design engineer Erich Übelacker, they instigated the idea of hanging Tatra’s air cooled twin in the rear of the T57. They already had the right engine for the job, and by 1930, rear engines were the hot new thing. This resulted in the T57 – V570, a cobbled-up two-passenger prototype. According to the definitive book “Tatra – The Legacy of Hans Ledwinka“, this occurred in late 1931.
Meaning after Mercedes had already built its all-new four passenger 120H prototype (left) and by which time Porsche was drawing up his T12 (right).
Ironically, the T57-V570 was unsuccessful, because the air cooling did not work adequately when enclosed in the trunk of the T57’s body, and thus the V570 was abandoned.
Tatra’s second effort was more ambitious, with a new four-passenger body that was developed with aerodynamic input from Paul Jaray. It too used the 854 cc boxer twin. This was the V570 prototype—never developed into a production model—and was completed in early 1933.
Again, that’s one full year after Porsche had built this very similar-looking T12 (1932), for motorcycle maker Zündapp. But Google “Tatra V570 VW” or something similar, and one will find dozens of articles claiming that the Tatra V570 was ripped off by Porsche and that the V570 was the true basis for the Volkswagen. Really?
Of course Porsche was influenced by Ledwinka’s work, to one degree or another, most of all the ducted forced-air cooling. There are other similarities that have been brought as evidence of the borrowing by Porsche from Tatra, such as his early use of twin transverse leaf spring for the front suspension, but that was being done by others well before Ledwinka, including the 1915 Cornelian (Porsche later developed his distinctive twin-trailing arm torsion bar front suspension). There’s the distinctive central backbone/hump in the VW’s platform chassis, but that too was used well before Ledwinka popularized it. And of course the same goes for the swing axle rear suspension.
Ledwinka and Porsche were friends going way back, and often met and discussed their work. As Ledwinka himself said: “Well sometimes Porsche looked over my shoulder and sometimes I looked over his”. Fair enough.
Coinciding with their early efforts at building their first rear engine car, in 1932, Tatra also embraced aerodynamics. We’ve shown that this was hardly new, but the interest in applying it was growing everywhere after Rumpler’s influential Tropfenwagen. Since Tatra had no experience with that, Paul Jaray was paid for the license to apply his principles to Tatra’s cars. Tatra and Ledwinka were aggressive patent filers, and in 1933, they applied for patents in Germany with this application titled “Improvements in or relating to Automobiles.” Take a good look at Fig.3.
Here’s Fig.3 along with another drawing of an extremely similar vehicle (top). Way too similar, actually. What is it?
Here it is, a write up of Tom Tjaarda’s “revolutionary” aerodynamic car in the July 1931 issue of Modern Mechanics, two years earlier. Rear engine, four wheel independent suspension…everything the Tatra streamliner would soon sport, even the dorsal fin.
Here’s Tjaarda with his “Sterkenberg” prototype. He didn’t find a manufacturer in the US willing to take on its further development or manufacture. And we know that Tatra didn’t pay him for using his design as their starting point,as well as in their own patent drawings.
In 1933, Tjaarda went to work for Briggs, the leading builder of all-steel and later unibody car bodies. There he developed this second version, shown at the 1933-1934 Century of Progress exhibition in Chicago.
Ford bought the rights this time, and it was majorly reworked into their 1936 Lincoln Zephyr, using solid axle Model T suspension and with a water cooled flathead V12 engine in front. America was not ready to join the rear-engine independent-suspension revolution.
Not even ten years later, with Tucker’s Torpedo, essentially an updated version of Tjaarda’s concept.
But Tatra was ready to dive in fully and quickly. Work started on the large T77 in 1932, and the prototype was finished in early 1934. It featured a 2.9 L air cooled V8, still looking still quite similar to the Tjaarda protype. It used transverse leaf springs in front, as that was still the most common way to achieve IFS, and in the rear it had quarter elliptic leafs as used by Rumpler.
The T77 was built in limited quantities from 1934 through 1938, and there were many variations in its body details, as this was essentially a hand-built car. Its excellent aerodynamics resulted in the ability to cruise effortlessly at up to 90 mph with only 75 hp. Of course it was expensive too, and as such we’ll leave it for now, and take it up again with Adolf Hitler.
Not surprisingly given its short gestation, the T77 had a number of shortcomings, including some very wicked handling qualities. And it was not suitable for serial production. So in 1936, the definitive Tatra, the T87, arrived; shorter without sacrificing much interior room, better visibility, and handled…a bit less wickedly. It quickly became the favorite of the SS. 
And it soon spawned a slightly shorter four cylinder version, the T97, which shared a number of body parts with the T87, but used a 1.75L flat four of 40hp and a top speed of some 80 mph.
The T97 is also often used in the conspiracy theories that it was the true basis of the Volkswagen, that the T97 was blatantly ripped off by Porsche to create the Beetle. By 1936, the Beetle was already on its third version of development, and getting quite close to its final one. Of course there are certain general similarities, but really only to those that think either of these cars were somehow unique. We’ve spent considerable time here showing that none of the features of them was unique, except in some details. And that Porsche started out in this line of development in 1931, a year or two before Tatra.
The T97 conspiracy theory is reinforced by the fact that Hitler did have its production ended in 1938 after he invaded Czechoslovakia. The theory says that he did that because the T97 was too similar to the Volkswagen, and thus would have competed with it. It certainly wasn’t because the T97 would actually present a sales challenge to the coming Volkswagen. The T97 was significantly bigger, a full six-seater, and priced several times higher than the VW’s planned price. And Tatra did not have the facilities to build the T97 or any cars in significant volumes. It was a low-volume producer and the VW was to be built by the millions.
By 1938, all of greater Germany’s economy was controlled increasingly by diktat, as it was in a massive military build up. Tatra, which also built trucks, became a significant military contractor, and it’s more likely that Hitler killed the T97 to make its production facilities available for that. He did keep the T87 in production as it was a favorite of his commanders. Ledwinka would be imprisoned for six years after the war by the new communist regime for war crimes.
As to the lawsuit brought against VW by Tatra, it had three claims of patent infringement: 1.) on the position of the engine (at the rear of the car inline with the transaxle); 2.) the location of the transmission; and 3.) certain details of the VW’s forced air cooling system ducting. Tatra’s patents on air cooling were so numerous that they essentially covered all the bases.
Porsche knew that there was no way not to infringe on the ducted cooling patents, as did Hitler, who told him not to worry about it, that the issue would soon go away. It did, when he invaded Czechoslovakia. But it came back after the war, in 1961, when the Düsseldorf Regional Court ruled that only claim #3 (details of cooling ducts) was valid, and VW made a settlement with Tatra.
After his imprisonment ended, Ledwinka moved to Munich where in his retirement he advocated tirelessly for the principles of swing axles on trucks (as Tatra trucks still use today), in order to improve driver comfort and for improved off-road adhesion. He did not share in the monetary settlement from VW, and refused numerous awards. He passed away in 1967.
It’s rather ironic that Ledwinka is so often identified with the Volkswagen—as its inspiration or ripped-off victim—considering that the well-documented timelines clearly show he was rather late to the rear-engine and streamlined party. And that he borrowed from others to be able to design and build his early streamlined rear engine cars. Presumably it’s because Tatra’s T77 and T87 are just so compelling. They were the first to be produced in any numbers, albeit modest ones, and as such are assumed to be the source of everything that followed in their delicate wake.
So the Autobahn and the Beetle were two parts of the same system, just as the record and the phonograph or the Web and the computer.
Streamlining isn’t needed for city cars or farm cars. It starts to make a difference at 40MPH and makes all the difference at 60. The Autobahn was meant to run at 60, which meant streamlining was necessary for the automotive part of the system.
Actually air resistance is a factor at all speeds, just disproportionally greater as speeds increase. Go walk into a steady 20 or 30 mph wind, and you’ll see what I mean.
True, but it’s not until 40/50 mph where air resistance becomes the main source of wasted energy.
Prior to that drivetrain losses make up more
However an EV produces fewer drivetrain losses so aero is more important. Hence aero wheels on a Tesla that you’re unlikely to see on an ICE vehicle.
But it does require energy, more energy than just overcoming frictional losses, from very low speeds already. A more aerodynamic car will be more efficient at 30 mph than a less aerodynamic car, all other things being equal. But yes, the effect becomes greater at higher speeds.
With the very low power engines of the times, aerodynamics was a more significant factor, especially in attaining higher speeds.
Another well-researched and logical article by Paul.
Hervorragend! Comprehensive, yet very to the point and enlightening. Lots of information I didn’t know about. Thanks!
Absolutely fascinating article, being read while I watch today’s Formula 1 race in the background. Glad that someone finally covered the entire chronology in reasonable detail.
Looking forward to follow up articles regarding the early post WWII Volkswagen.
I’m a bigger fan of the article than I am the race! It looks like another Hamilton runaway; I wish one other manufacturer could give Mercedes a real run.
Nice work, Paul – I’ve always been merely superficially knowledgeable about the gestation of the Bug, so I learned a lot.
Achh, no spoilers! I’m on the West Coast and just finishing my coffee before watching…
The best race of the weekend turned out to be the Baggers race at the MotoAmerica Superbike Weekend at Laguna Seca. The entire race is on YouTube, you haven’t seen racing until you watch Hayden Gilliam’s sliding a Harley Street Glide into the curves like it’s a 1000cc sport bike.
Absolutely fantastic read!
I would suggest a nuance to the proposition that Hitler was the Father of the Volkswagen, in that, while there is a definite parallel to Ford’s vision of mass-produced vehicles that ‘everyman’ could own, Ford was also the force behind the design and manufacture of the Model T. His vision was realized by one person, in other words.
Hitler had not the capability to design the product and manufacturing system and had to rely on a second party (Porsche, although he certainly could have chosen another person/firm) for that aspect of bringing the Volkswagen concept to reality. So your caption above, “The proud parents and their baby,” is actually spot on to the nuance I’m suggesting.
A separate question is related to your comment about VW air-cooled engines still being produced today. I was under the impression that production of engines (spares?) stopped in 2006, not long after the Type 1 Beetle ended production in 2003.
Again, excellent article and a real showpiece for CC.
Well, yes, that’s why I made them both parents.
One can still buy brand new air cooled VW engines, just not from VW. 🙂
https://darrylsaircooled.com/
The cheapest one is $4300.
Yikes!
Ed, I’m not sure if this qualifies as “still being produced”, but I’m fairly confident that I could go to any of a number of aircooled VW vendors’ websites and purchase every single component of a VW Type I engine in brand-new condition and assemble one from scratch.
And Paul, I found this a well-written and insightful treatise. As you pointed out early in the article, there are really very few truly new ideas. Most everything that is touted as “new” is just a new combination of existing ideas, and the “Beetle” is no exception to that.
What Hitler did as a dictator was to compel various people to make it happen. My main takeaway from this post, and the truly new piece of information that I gained from it, was that most of the startup and overhead costs were separated from the production costs. Perhaps that’s just a trick of accounting, but it seems easy to build a car cheaply and profitably if one does not have to factor startup and overhead costs into the profitability figures. If Henry ford had been “given” his production facilities for free by the government, the final pricing of the Model T might have been $150!
If Henry ford had been “given” his production facilities for free by the government, the final pricing of the Model T might have been $150!
Given the massive profits Ford was banking from the T, he probably could have sold it starting at $150. 🙂
Your point is valid of course. But there are certain fundamental differences between the US in the 1920s and Germany in the 1930s that make direct comparisons difficult. And the VW was a more complex and sophisticated car, with a modern all steel body.
Although a T two-passenger roadster was priced at $260 in 1926, the enclosed sedan cost $660 dollars, almost three times as much. And a Ford two door sedan still cost that much in 1939. So one really needs to compare the sedan to the $250 Volkswagen.
I’m not so sure that “free” factories would have impacted the T’s price so much. Volume was so high, staggering, that per-unit cost amortization of even the most significant investments might be surpringly little.
For example, using rough figures, if some investment of say15 million dollars was amortized over the T’s entire run, it’d only be about one dollar per unit.
It’s my guess, but wasn’t the entire Highland Park plant probably launched for well south of 5 million?
I don’t have the figures readily available. But yes, my conjecture is that the investment in Highland Park was quite modest in relation to the gusher of cash it produced. Profit margins typically were much higher then. GM assumed a 30% profit margin as a minimum on any program.
It’s like it was once upon a time in the PC business. And how it still is in the iphone business.
Car companies are very happy to hit a 10% profit nowadays.
You’re correct, Evan, in that there’s still widespread parts support for the VW air cooled engines. My point was that VW is no longer producing finished engines nor spares. Darryl’s (and likely others) are building up “zero time” engines from what has to be a combination of NOS and aftermarket components, and in fact, the Darryl’s web site has a buried “small print” statement that some parts are NLA as ‘new’ and refurbished used parts will be substituted in those cases.
You can if you so desire buy an entire reproduction 23 window van its a convoluted system getting the roof panel window holes pressed but it can be done the entire vehicle can be sourced aftermarket so all you have to find is an existing vin some spot welds and hey presto one valueable VW van.
Fantastic read tying all the various parties together. As you said there are numerous outlets offering one aspect or another but I haven’t come across (or looked for, to be truthful) one that takes it in all these different directions.
Most interesting that the shape is representative of (and demonstrated by) numerous different parties working using the same general knowledge set and that it’s really less of a “designed” shape than a natural shape.
An excellent way to start my Sunday, a strong cup of coffee and this comprehensive treatise. Thanks Paul! I knew about bits and pieces of this, but all together, it makes a cohesive story. New, and surprising to me, was that the terms “volkswagen” and “kafer” were in common use long before being applied to the VW Beetle. A couple of other observations: as the owner for ten years of a Ford truck with Twin Traction Beam front suspension, I can see the benefits of swing axles, though they have some flaws in a steering application. And after seeing all the backbone chassis, I think Colin Chapman too was influenced by this school of European design. Finally, I suspect that to Americans, even car enthusiasts whose knowledge of history may have been limited by difficult access to books in the pre-Internet days, the Beetle’s shape and technology really seemed unique. So without knowing the context and environment of the time in Europe, we assumed it sprang fully formed from one person’s mind.
Paul, thank you! You got my Sunday good start by keeping me away from the news as I had my coffee. I’ll sleep better tonight because of that!
The intertwining of tech with the people that create it and the conditions of the time is so interesting.
Quite an interesting Sunday morning read – two cups of coffee!. I knew about some of the original concepts behind the VW and the people involved (Porsche, Ledwinka, Kommenda) but your article went much more in depth and ties them all together very well.
What a fabulous read! Your research into this topic shows clearly. You prove what everyone tends to forget – history is complicated. Every idea is born in a stew of other ideas. Our natural tendency to look for a linear story often obscures much of what was happening all around the central narrative.
I would argue that the Model T was quite innovative in that it was among the first to marry cutting-edge engineering and technology (as of 1908) with a small, lightweight package. The Model T was a far better car than many costing many multiples of its price. But as you say, it’s original package was more of a middle-class peoples’ car rather than a real “peoples’ car” in the way the VW was intended.
It is interesting to contemplate how the program might have progressed (or not) under someone other than Porsche. His age, personality and capabilities seem to have been uniquely shaped to make a fit with the mercurial (yes, let’s go with that) Hitler.
Agreed about the T. My point was that Ford didn’t try to reinvent the automobile, he refined and improved upon the basic concept as it was at the time. Of course that was still quite new in 1908. I’m hardly faulting him for that. But as we saw from Lanchester in England, some were already building cars in 1908 that were radically different from the conventional format.
The stream of thinking that led to VW was based on the premise that the conventional (front engine, frame, RWD) approach was obsolete, and that a new basic format would offer both lower cost as well as improvements in comfort, efficiency and ride.
That led to the rear engine, backbone frame and independent suspension all-round. As well as FWD with makers like DKW and Citroen.
What about Béla Barényi?
Didn’t he play a role in the history of the KDF-Wagen?
Did you miss it? It’s on page two, in the Josef Ganz section.
A beautifully written and illustrated article. The Fiat pictured bears an amazing resemblance to the contemporary Fiat 500.
WOW! Paul, you have outdone yourself. Have you been considered for a professorship? Despite that I have much work to complete today, I could not stop reading this article.
Great read!
To get ainto a a bit technical detail, the axle seen in image #12 was probably not so ingeniously simple and reliable as a casual glance might indicate.
Think about it… if the twin ring-gears were a matched set and in mesh with the driveshaft pinion, then the motion resulting from shaft rotation would either be counter-rotation of the axles, or lock-up. For the “twin gear” to work only one ring-gear could be driven by the drive shaft (now we have major thrust to retain) the other would have to be driven via at minimum one idler, to reverse rotation.
Then, for the ring-gears to be able to independently arc around the drive-pinion, they could not share a common case, housed in the usual rigid carrier. Without the rigidity of a carrier-held case, maintaining proper tooth contact would be a nightmare. The slightest wear at the shoes and proper gear mesh is out the window.
For a century now, from garden tractor to earthmover, has anybody successfully challenged the proven case/carrier combination for final drive design? Does anybody know of a production example?
To me, the “sliding shoe” design seems like some of DaVinci’s work… great concept if you can wait 500 years for others to iron out the details. Suddenly a conventional differential with axle joints isn’t so complicated.
As far as I’m familiar with VWs, which would be US version ’50s on, VW swing-axle cars used a conventional differential with a “screwdriver tang drive” joint at the axle. Did some in the old country use the “twin gear” concept?
Tatra trucks still use that style of swing axle design even today, on their very heavy duty off-road capable trucks (image below). But yes, there are other versions, and the VW uses what you describe. But it’s still simpler and more rugged than CV joints used to be, although today CV joints have become very long lasting too.
CV joints made properly out last the vehicles they are installed in, I made enquiries about new CVs for a mates Xantia only to be told we dont sell them by the local agent so what ever the noise is in the left front it isnt that,
JimDandy,
Your comment: ” For the “twin gear” to work only one ring-gear could be driven by the drive shaft (now we have major thrust to retain) the other would have to be driven via at minimum one idler, to reverse rotation.”
Let me attempt to describe the system in this manner;
There are 2 axles, one on each side of the center diff. They are free to swing up & down on an arc that keeps the centerline of each axle’s ring gear in the same position. The drive shaft enters into the diff housing from the front. There is a pinion gear at the front area. Looking forward, this pinion gear is in mesh with the left axle’s ring gear, but not the right axle’s ring gear. No matter where on the swing arm’s arc, that pinion gear will be in mesh with the left axle’s ring gear.
Now let’s look at the center drive shaft inside the diff housing, at the point just to the rear of the pinion gear described above. The center shaft continues to the rear of the diff housing, where another pinion gear is mounted, this pinion gear is in constant mesh with the right axle shaft’s ring gear.
As the input shaft is rotated clockwise, the left pinion gear rotates clockwise as well. causing the ring gear to rotate forward & downwards from the top.
The rear pinion also rotates clockwise as it’s on the same main shaft in the diff. When it contacts the ring gear for the right axle, it causes the ring gear to rotate upwards & forward, the same direction as the left axle.
To keep the systems from interfering with each other, one of the pinion gears is slightly smaller in diameter than the other, with the 2 ring gears sizes matching their respective pinion gears. [The larger pinion gear powers a smaller ring gear, and the reverse difference for the opposite ring & pinion set.] Because the ring & pinions are of different sizes, the sets don’t come in contact with each other.
It’s sometimes difficult to envision, but I’ve not been able to find a simplified power diagram online, that visually shows how the Tatra swing axle system works. [It may be because I’m searching in English!] I’ve hadthe transaxle apart on my Tatra 603, and the clearances are so small it’s hard to see the offset between the gears, but I can tell you each side doesn’t interfere with the other!
And of course, from the engine, thru the gearbox, the differential, and out to the rear wheels, there are no u-joints, no CV joints, no T-joints. I’ve seen Tatra big truck chassis units, up to 6 axles with all wheel drive. and not a u-joint in sight.
On Youtube there are a few great videos on the Paris-Dakar races, and it’s possible to see these trucks in extreme use.
Great job, Paul! How many hours did you spend on this? 🙂
Disclaimer: I’ve never studied German. Your comments about the difficulty of conveying the nuances of volk reminded me of a passage in William L. Shirer’s The Rise and Fall of the Third Reich. Shirer said that Mein Kampf refers to the “folkish state” a number of times. (I assume that German for “folkish” would be volkisch.) Shirer went on to say that he had read Mein Kampf multiple times, and he never quite understood what Hitler meant by the “folkish state.” Of course it makes sense that if volk is hard to get one’s head around, “folkish state” would be likewise.
It’s a loaded and complex word. The variations of its meaning are best perceived in their context. One only needs to hear Hitler give a speech to get the gist of what he was implying with that word.
Ultimately, it’s the very essence of what Hitler was all about. That word encapsulates him.
This is yet another amazing piece of work, Paul, and thank you for it.
The Beetle is always a car that evokes strong emotions. I was never into them as I like heat in the winter, but the following is huge.
The Beetle is the only car I can recall repeatedly hearing “I wish VW would make them again.” I recently spoke with an acquaintance who thought the end of the air-cooled Beetle was a giant conspiracy and that Beetle production would commence pronto once the conspiracy was exposed.
I replied that I didn’t think there was much of a market for a 90 year old car.
I like heat in the winter, passive safety, performance, good handling, room, and refinement!
As conspiracy theories go, that one is pretty benign. I wish a lot of people would trade in their current conspiracy theories for that one.
Thank you Paul for a very well researched and presented article.
If you want to create a Volkswagen, better be born in Austria-Hungary. Either Vienna (Rumpler, Jaray, Ledwinka), Moravia (Porsche, Nibel) or Budapest (Ganz). Wouldn’ t hurt if you came from Braunau. By the way, I believe Josef Ledwinka and Hans were cousins.
Seems to help for Model-T designers too; Galamb, Farkas.
What a great article! Good to see Rumpler receive praise and Ledwinka reassessed. All designers pinch good ideas, just like all creative people so this clearly shows the contributions each made.
I wonder if you could do a similar article on Issigonis and the Mini? It seems to come
have out of the air but of course it didn’t, but its antecedents are rarely considered. Like the Lloyd 650 from Grimsby with its transverse front wheel drive.
I wouldn’t want to live in a town populated by Standard Superiors after watching that car in the video.
What a fascinating article to read this weekend. I knew only a bit of this history before — so it was quite a treat to sit down and read this fantastically in-depth and well-illustrated history.
I’m amazed at the 10 engine flying wing with seating for 175 that Rumpler designed. That guy certainly was ahead of his time. Thanks for your hard work in presenting this.
My goodness, you’ve excelled yourself here sir, almost meeting the standards of Proffs Adreina and Tatra.
Jokes aside, serious congratulations Paul, it’s really quite something. I will have to go back and read more thoroughly (and links, etc) over the next few days, but wanted to convey my appreciation for your effort.
Two quick comments for now. One, that V1(!) chassis drawing by Porsche has restraining mods for those verdammte swing axles: I wonder if cost eliminated them later, but surely it indicates an awareness of the safety issue early on (of no consideration for the “expert” driver – real or not – and monied buyesr of racers or luxo cars).
Two, could it be said that Jaray is the biggest influence of all? He is quite the linking character, and his aero ideas seem a big driver of rear engines, which other wise don’t (to me) have any obvious advantage from a cost/design point of view back then.
Again, my congrats, Dr Dr Proff N. Prost!
Good catch on the restraining straps. I don’t know why they went away. it might be a question to pose at thesamba.com. Perhaps I will.
Perhaps, re: Jaray. He certainly popularized aerodynamics. But the Rumpler was also employing it very successfully, except he used it more in the plan form than elevation form, which rather works better for most cars.
As I understand it, the Lincoln Zephyr did use some form of unit body, sometimes described as bridge-and-truss, rather than a conventional frame, except on the convertibles.
True. I forgot about that.
Great read Paul but I have to go to work I’ll reread it later, Ive seen most of this before of course but never the tie ins to the VW, But that W engine layout has been refined and is in production currently awesome stuff for the braincell at 2.30 am Thanx.
Fascinating, thank you! As a former driver of your favorite version (1966 1300 cc) purchased new by my dad. I knew a fair bit of this history, but not all the people involved or their connections. Will re-read and forward to other “car nuts” who may not regularly read this blog.
Paul, a truly absorbing read. Fine work on all counts. By chance my brother, an owner of several air cooled VWs in the 80’s sent me a copy of Walter Henry Nelson’s “ “Small Wonder – The Amazing Story of the Volkswagen” that I just received today. Your work surpasses his first three chapters by a long shot in it’s depth and detail.
Thanks.
I had that book quite a few decades ago, but it got lost a long time ago. It was the first book to write the story, but more historical details are still being uncovered.
Paul:
I loved learning from this piece, thank you. Took me a day or so to have the time to read; the wait was worth it. The writing provided much clarity to a era I understand a little bit better now.
It’s a bit of an overstatement to say, as to the KdF-Wagen “savers”, that “their payments were honored some years later by VW after the war.” Initially, Volkswagen AG denied any liability, and a group of “savers” sued, demanding delivery of brand new Beetles. There were lots of legal issues. Who did the “savers” have a contract with? The Nazi Party? The Labor Front? The Reich Government? And was postwar VWAG a legal successor having an obligation to perform on the agreement?
Ultimately, after lengthy litigation, the suit was settled in 1961 with an agreement that gave savers who had completed their payments a 600 DM discount off the price of a new VW. I wasn’t able quickly to find the price of a Beetle in marks in 1961, so I can’t say what the 600 marks represented in percentage terms.
The funds were held by the KDF. And the Russians stole the money (a huge amount) from the KDF accounts after they took Berlin. The Volkswagen company after the war was a completely new entity, created several years after the war ended, when none of the Allies wanted the factory or its contents.
Legally, one can certainly argue the the new VW company had no liability for that. But as you said, eventually VW did offer a settlement.
This was a complicated issue, given the history and the war. The settlement seems reasonably fair to me. A whole lot of folks lost everything in the war. That wasn’t exactly the fault or responsibility of the post war Volkswagen Werk.
Fantastic article, Paul!
As an ex Porsche Mitarbeiter and daily driver of an air cooled VW, I found this article absolutely fascinating. This is a fine piece of automotive scholarship.
I have read the Ganz book, am a great fan of Ledwinka’s work at Tatra and familiar with Rumpler and the rear engined Mercedes, but the way you have woven these themes together to form a logical conclusion is…ausgezeichnet!
Excellent article, most enjoyable read. Ford and Hitler had a lot in common in their world view. People who yearn nostalgically for the Beetle have obviously never driven one in modern traffic or in the rain. They are slow, lethal contraptions clearly built down to a price. That said I did have a yearning for a super beetle recently (I too suffer from the ‘car whore’ syndrome), but fortunately it passed.
Hi Rob,
Hi Rob,I drive a descendant of the Kdf (Karmann Ghia) in modern traffic as my DD and it copes surprisingly well. It will hold 75 on the freeway and it’s quick enough in town if you drive it correctly. It is a charming and fun ride, although the sidewind stability and heating and ventilation leave a lot to be desired!
Passive safety is non-existent compared to moderns, but mechanical parts availability is excellent and they are easy enough to work on.
They were definitely not built down to a price – the finish and basic quality of the VW was excellent in its day.
Having driven other European cars from the immediate post WW2 period, VWs must have seemed incredibly modern in comparison, especially to things like the English Ford Popular or Morris 8s with their beam axles and wheezing, maintenance hungry side valve motors…..
Paul, you’ve raised the CC bar higher again, much higher. Probably the most authoritative piece on a specific car we’ve ever had, maybe that I’ve read online, and the amount and quantity of the research and analysis is truly significant.
The general theme that the Beetle had many influencers shaping it over an extended period is as plausible as it is unsurprising when you pause to consider it, but identifying them all and linking them together in a coherent sequence and argument is not easy. Terrific work, Paul, and thanks for doing it, and adding the social context around it too.
The final nominees maybe the one some would have expected, but the important part is to put it all in context – Car nut nationalist (and worse) dictator wants a modern, nationally identifiable car for his people, and will design and impose an economic and manufacturing system that will enable it, empowering a leading engineer, himself a bit of an outsider through not being attached to a key manufacturer, to execute it, whilst not worrying too much about adopting best practice and blurring the edges of patents.
Do you have a recommendation for a book covering the post war history of VW, the Wirtschaftswunder and post war rise of the Germany industry? It’s a fascinating subject
What a well-researched essay, Paul, thank you. A great assemblage of relevant photos along with a deep dive. One of your best.
Thanks Paul, I had skipped this one originally to save for when I had more time. (And forgotten about it, thus proving that end of year best-of articles are a good idea)
“Small Wonder” was in the University library back in my engineering school days, and I recall finding and reading it one night instead of studying. Really great detail in the way your article weaves together the threads, and I hadn’t realized how Hitler bypassed the entire German auto industry to get the vision done. Fascinating stuff.
Overall the story brings to mind the “Connections” series done in 1978 by James Burke for BBC. We watched it in our Engineering & Society class, it shows how technological advancements are build in other work and more interconnected than the single parent of an idea, and it’s still an informative and entertaining watch.
Fantastic article Paul I reread it this time round even knowing it is a retread, one thing I have wondered is the VW was designed to run at a steady 60mph on relative flat roads autobahns would our lower speed limit and hilly terrain be responsible for relatively short engine lives in Beetles less cooling air and having to work harder hill climbing, some didnt do big mileages between rebuilds at all, some ran seemingly for ever. Or was it just driver abuse and neglect.
thx