... when built in 1909 onward. The Blitzen Benz, a 21.5 litre four-cylinder sporting jalopy made to go fast in a straight line, did 141mph in 1911, faster than any train or aircraft of the time.
It looks strangely delicate in its photo, but it's a colossal monster with exposed drive chains. Friction dampers if any... holy cow, would have taken some guts to really extend it.
I am indebted to the Telegraph motoring supplement for the Andrew Frankel piece and winsome photo.
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Three quarter rear view, no driver.
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Photo...............................NOW!
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You know I'm helpless with this sort of thing. Telegraph website maybe...
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Heh heh... pretty isn't it?
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It's always interesting to look at the early adventures. There wasn't much systematic engineering, even less consideration of the principles of physics, and the thought of any type of optimisation many years in the future.
As an example of this "common sense" applied to vehicle design is the use of brakes on the rear axle only. The very axle which is the root of yaw instability in vehicles!
If you are only going to put brakes on one axle, then, to maintain yaw stability, it must be the front!
I wonder what we're doing today that engineers of the future will find laughable.
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>> I wonder what we're doing today that engineers of the future will find laughable.
>>
Running signals through a body control module to tell the computer you want to turn the lights on instead of a simple switch, perhaps?
Chrysler, for example,call theirs a TIPM (Totally Intelligent Power Module)
Really?
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Torque and more torque, 21.5 litre 4 pot, yes please.
I bet it needed chain drive, how thick would a prop or how large a final drive need to be to cope.
Don't think white does this beauty justice, should have been an angry matt black or the deepest red the devil himself could muster.
Last edited by: gordonbennet on Sat 5 Oct 13 at 21:33
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If you are only going to put brakes on one axle, then, to maintain yaw stability, it must be the front!
I believe in the early days of motoring, brakes on the front wheels were considered dangerous. Even in 1930, the front brakes on my car aren't really that good but the back brake is capable of locking the wheel on dry tarmac.
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>>I believe in the early days of motoring, brakes on the front wheels were considered dangerous.
Yes!
One of the perks of working at the Polyversity is that I get access to the online archive of the IMechE, going back to the midle of the 1800s. It's remarakble to read the older papers presented to the institution on the subject of vehicle design.
It's no great surprise to find that significant jumps in the systematic application of scientific principles happened during periods of conflict.
In my work, I find the papers published between the end of WW2 and the mid 1980s are most useful in helping students. These papers were written with the aim of exaplaining the application of theory, wheras more modern papers tend to describe some small incremental advance, or some small development in computer algorithms for use in various ECUs (good stuff for the companies and the customers, but useless for students!)
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Yaw stability isn't everything N_C. I have little doubt that front wheel brakes were tried in the early days of motoring and that it took some time to get them to work properly. Even when new, cable and rod systems for operating front brakes would work differently with e.g. different steering angles applied, in extreme cases perhaps resulting in one front brake locking or snatching. That would rightly be perceived as dangerous, and might even exacerbate any yaw tendency!
Even hydraulic front drum brakes, if cheap and badly worn, could apply one at a time causing a wriggle on initial application. People really really don't understand what a quantum jump in safety, practicality and ease of maintenance discs were.
And surely this yaw business only applies in desperate situations when the driver has locked the rear wheels. That Blitzen Benz, I read, has its brakes applied by hand, by pushing not pulling the lever. But they hardly work anyway, so that's all right then, safe as houses.
:o}
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Pictures of the 24 litre BMW powered Brutus here www.topgear.com/uk/photos/BMW-Brutus-pics-2011-07-11
There was an item in one Top Gear where this car was compared with another aero engined monster but I don't recall what the second one was.
There was also John Dodd's "Beast" which had a 27 litre Spitfire engine and was road legal. This picture shows it after he had been forced by RR to remove the RR grille from it, they objected as they said it wasn't built by them. tinyurl.com/poww2lg
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>> Brutus
>> John Dodd's "Beast" which had a 27 litre Spitfire engine and was road legal.
Yeah Mellers, but those were specials. That Blitzen Benz was state of the art from a top maker at a time when a land speed record holder could also be a road car, albeit more or less a supercar. Equivalent of something between a late mid-engined V12 Ferrari and a Porsche 917 with an impure dash of Richard Noble's jet car...
I can't get over its elegance, or the fact that that fabulous flame-spitting motor was purpose-designed for the thing.
It obviously had hopeless damping. One example bounced so badly over the Brooklands banking bumps that it went over the top of the banking at 120 and was 'smashed to bits' without killing the driver (no mention of the riding mechanic though - perhaps there wasn't one at the time).
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>>Yaw stability isn't everything
So, that's why rear brake locking is prohibited by UN and EEC regulations? That's why mixing crossply and radial tyres the wrong way round was an MOT fail?
The massive danger in losing yaw control, particularly on a car like you began this thread with was rolling over, which, looking at the cockpit of that car would be difficult to survive. So, I would suggest that in a car like that, yaw stability really was vitally important!
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>> that's why rear brake locking is prohibited by UN and EEC regulations?
Good heavens N_C! Do you mean people doing handbrake turns are violating the UN Charter and EC law? To the gibbet with them!
A measure of yaw stability in the Blitzen Benz is ensured by the uselessness of the brakes. This probably applied to quite a lot of early cars with rwb only. One can only assume that the less cretinous drivers of the period learned to cope and drove accordingly.
You would have to be quite brave, or confident, to drive a veteran or vintage open-topped sporting vehicle in real anger, admittedly. But of course the cars didn't have seat belts so with luck the driver would be thrown out when he rolled the thing. The sort of injuries he might suffer are beyond thinking about, but many survived and continued to dice with death.
It's possible of course to fit roll bars to protect drivers, but fortunately the owners of the better vintage sporting cars don't seem to do it. I've never seen a Bugatti or Bentley with roll bars for example (and a good thing too because they would look horrible).
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I expect the torque of that monstrous engine also meant some serious engine braking, well at least down to its minimum cruising speed of 40mph...
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Blitzen Benz sounds funny,blitzen und thunder those Germans are clever.
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It's possible of course to fit roll bars to protect drivers, but fortunately the owners of the better vintage sporting cars don't seem to do it.
Have a look at vintage racing in the USA. Rollover bars are commonly fitted, and I think are compulsory for most forms of racing with them.
Trouble is a rollover bar makes rolling over more likely as it raises the centre of gravity. Quite a few vintage chassis', are not suitable either, apart from the fact it looks very silly.
Last edited by: Slidingpillar on Sun 6 Oct 13 at 13:06
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I seem to recall a tale of a ? 1970s touring car racer who made his rollcage from exhaust pipe tubing to save weight - was found out after an accident he managed to survive.
Last edited by: Lygonos on Sun 6 Oct 13 at 21:31
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Fastest machine on earth - R.P.
