Thursday, September 20, 2007


One of the ways we English like to exert our supreme place in history, is to look over our glasses, and ask someone a simple question which confirms our Top of the table position – like “Name three famous Belgians”.


And when you’ve got your (very short, I suspect) list, you then have to remember that Poirot was actually a fictitious creation of Agatha Christie, so pass the rubber please, and try to think of a third (or even a second) name.

In a similar vein, write down the names of a dozen famous French Engineers. In the vehicular arena, Citroen, Renault, Bugatti (except, of course, he was Italian), the guy who designed the TGV (except that you don’t actually know his name), Bleriot and Dassault in the aviation field, Eiffel, the fellow who designed that glorious bridge they’ve just put up in the Dordogne which is so high it seems to live in the clouds (actually that was Sir Richard Rogers, who sounds to me to be a tad unFrench). Now I’m struggling. Except for one man.

Anyone heard of Andre Chapelon?

If you look at the way Industrial and even Social development has spread across the globe, you don’t have to think for long before the overwhelming impact of the railways on it all looms large. Just look at the UK, with the unbelievable speed at which the railway track engulfed the country in the first part of the Nineteenth Century. Compare it (and cry) with the way we do it with roads in the 20th and 21st Centuries. The Victorians certainly had something we don’t have today.

It wouldn’t be too difficult to argue that without the railways, we would be a century behind where we are now. They gave us the ability to move huge quantities of goods quickly, reliably and cheaply around the country, and I suspect some University graduate has already got his First with a dissertation showing that Britain’s headlong rush into track-laying was one of the major issues which gave it a decisive edge over all other nations in its Industrial development.

But when you look at the railway engine, as a piece of Engineering design, you sometimes wonder how it got developed over the last seven or eight decades of the Nineteenth Century. Most of the designers simply seemed to copy what had been done before, but making it a bit bigger and longer – trial and error was the watchword. Brunel sticks his head above the parapet with the brilliant idea of building a Broad gauge (7 feet) track, rather than the “Conventional Wisdom” version of 4’ 8½”, which was standard everywhere else in this country. Can you imagine today how the railways would have looked if his logic had held sway?

But for the most part, the railway engine development was a classic example of “suck it and see”. Try this bit a bit bigger – if it works, keep it, if it doesn’t, try something different. There was a conspicuous lack of scientific intellect, or of going back to first principles, used by most of this country’s Chief Railway Mechanical Engineers.

So we got engines which worked, but no-one really knew exactly why. They lacked the power they should have developed, and they were far more inefficient than they could and should have been.

Back to the beginning, and enter Andre Chapelon. He was a Frenchman born in 1892 in the Loire valley. He developed a fascination bordering on a passion for the steam railway locomotive as a very small boy, and this obsession led him to a life as the greatest railway engineer since it was invented. Although he passed his first Bachelier exam with the rather nice comment of “Assez-Bien” (literally “Good Enough”), he went on to take higher exams in one of France’s Grand Ecoles.

In the early part of the Twentieth Century in France, you had to serve two years in the Military, and a further three years studying. His military service coincided with the First World War, and he ended up being a technical trainee, up in balloons working out ways of dramatically improving gun-fire accuracy. Some ten years after all this started, he returned to the Ecole Centrale and graduated with the rather nice title of Ingenieur des Arts et Manufactures.

Just after the end of the First World War, the French Railways were organised in a similar way to the British ones. In the UK we had the LNER (London and North Eastern Railway), the LMS (London, Midland and Scottish) the Southern, and the GWR (Great Western Railway, or God’s Wonderful Railway if you lived anywhere near Bristol or the West). The French railways were organised in a similar fashion, and Chapelon joined the Paris-Lyon-Mediterranee Railway as a probationer.

The thing which struck Chapelon from Day 1 was the lack of scientific method being used both in the running of the railway and the design of the engines. He had read, and it seemed understood the teachings of people like the thermodynamicist Nicolas Carnot, who had died almost 100 years before, so it’s difficult to argue that the information had only just become available.

He seemed to be alone in realizing just how fundamental Carnot’s ideas were as a key to the understanding of the workings of a steam locomotive. He found it quite amazing that a major institution like the PLM should be so ignorant of the simple (!) rules of Thermodynamics. The simple fact was that every other railway company in the world was in just about the same position. They did it the way they did it, because that was the way they had always done it.

Thanks to a judicious word from his University professor, he soon found himself attached to the PLM’s R&D section, and was soon given a small section of the department to run, looking after engine trials and exhaust systems.

Now, French railways operate differently from those in the UK. In the UK we were used to light trains running frequently between the major cities. In France, they ran trains often more than twice the weight of their UK equivalents, but running far less frequently. This demanded higher powers to operate, and as train weights inexorably increased, so the need for more and more powerful engines appeared. In France, they almost always used a Compounding system where the locomotive has two sets of cylinders, a High Pressure and a low pressure set where the steam from the High Pressure cylinders, rather than being exhausted to air, is fed into another set of Low Pressure Cylinders to extract more work from the energy in the steam. More complicated than the UK style where only one set of cylinders is used – but more efficient.

Chapelon started to look at the PLM’s engines and soon found areas where, by applying what to him were simple changes, he could literally transform the performance of their existing locomotives. He developed, with a Finnish engineer, a new form of chimney, which made massive differences to the engine’s output for very little cost. This no doubt endeared him to the Company’s Management, because they could “get something for (almost) nothing” and avoid the wholesale construction of an expensive fleet of new engines. It goes unsaid what the Chief Engineer who designed the original engines he transformed, thought about it!

His fame spread as he applied his principles to locomotives throughout France, where, by rebuilding according to Chapelon’s ideas, power improvements of 50% were often achieved. He also improved the Operating costs and efficiencies of these engines by 20-30% - quite remarkable figures.

He led the creation of a Testing Plant at Vitry near Paris where engine testing could be undertaken under controlled conditions, whereas before they had to be tested using undulating track, with varying weather conditions – simple and obvious, but, once again, no-one had done it before.

The Chief Engineers of the four UK Railway Companies soon got wind of this. Led by GJ Churchward of the Great Western, and closely followed by all the others, they all set off to France to understand what effect Chapelon’s ideas could have on their own creations. Some of them took their engines over there to be tested and the answers came back as to what improvements could be made – A Lot.

Many of the existing UK engines were then rebuilt using Chapelon’s ideas, and many of the new designs which followed took up his principles to huge effect. There is probably no engine designs in Western Europe after the first World war which were built without taking on board Chapelon’s ideas.

Meanwhile, he kept building more and more powerful engines to operate the continually increasing size of passenger and freight trains that were needed, and towards the Second World War, his greatest designs were produced.

There are few people who would not cite one of his designs as the Ultimate Steam Engine - Ever. To us in the UK, with all their pipework on the outside, rather than hidden away as the British tradition demands, European locomotives look a bit of a mess, and a bit second rate. Every engine in the UK worth its salt boasted a name. We had the Coronation Scot, the Kings and Castles, the Battle of Britain, and the A2/3/4 classes including Mallard, Silver Link and Flying Scotsman among their strength. As far as I can discover, not a single French engine ever had anything other than a difficult to decipher number.

So when Mallard flew down a long gradient near Grantham pulling a couple of carriages at a speed no other steam engine had ever reached (and still hasn’t), we thought we were the bees knees. But blasting down a long hill pulling next to nothing is not the way you measure the quality of a steam engine. What you do is put a mercilessly long train behind it, point it at a long hill and see what it does then. That’s the real world test, and guess whose engines come out top, pound for pound here?

Monsieur Chapelon wins by a country mile, perhaps kilometre.

Even in terms of aesthetics, to this author’s eyes at least, Chapelon’s Pacifics and, above all, his romantically named One-Off pi├Ęce de resistance 241.A.1 are the most beautiful engines ever made. They are also, in most engineer’s minds, simply the best engines ever. Pound for Pound, they are the most powerful and the most efficient ever made. This engine was the raiwayman’s Concorde.



To give this statement some scale, the French Loading Gauge is only slightly bigger that the British one, so you can draw a reasonably valid comparison between something like the British Coronation Scot and Chapelon’s 241.A.1. In terms of power output the Coronation Scot could produce around 2,500 Horsepower, and that on a bit of a transitory basis – Chapelon’s 241.A.1 could produce in excess of 4,000 Horsepower continuously. The French engine used around 20% less coal and around 40% less water than the British engine, which was usually accepted as the most powerful passenger engine in the country. Those are not small differences.

Chapelon’s problem was that he was building these engines just at a time when the world wanted to turn to electric and diesel traction for its railways. An objective comparison between steam and diesel/electric traction would put them much closer in operating costs that the politicians wanted, so the Steam vs Electric/Diesel reviews were loaded to give the answer they wanted, and Chapelon’s ideas for further revolutionary improvements came to nothing, at least in Europe.

Almost every engine he had worked on in his life was a conversion from something else. Even the glorious 241.A.1 was modified from someone else’s less than successful design. When he was given his head to design something from a clean slate, something wondrous appeared. He demonstrated that he could build steam engines which would be capable of producing 6,000HP, and to understand what this means, the UK West Coast main line, some 50 years later, has only just, in the last three or four years, moved on from Electric engines producing 3,300HP.

In the typical French way, where some things they do better than anyone else in the world, and in others you simply wonder about their sanity and stupidity, the only example of this remarkable piece of engineering in existence was broken up in 1960. Only pictures of it remain.

Bring back the guillotine!

But it doesn’t stop the thought that here was a man who, in his field, and it was a major one at that, was the best Engineer ever. He advanced the railway engine by leaps and bounds, like no-one else. He fundamentally influenced every railway engineer in the World, both of his time and those who came after him. And he built beautiful engines which were a world apart from anything anyone else ever made.

And because he was French, few people in this country have even heard of him.

It does make you wonder that Monsieur Chauvin, of “Chauvinism” fame was actually French – he should have been an Englishman.



1 comment:

David Elvar said...

I can't help but agree with every word of this. Chapelon was an absolute genius in any sense of the word and deserves wider acknowledgement of his achievements and ideas. A great pity that his last design, the 2-10-4, never saw light of day. I suspect it could, even today, give some of the more modern freight traction around a run for its money.