André Chapelon
Encyclopedia
André Chapelon was a noted French mechanical engineer and designer of advanced steam locomotive
s. Engineer of Ecole Centrale Paris
, he was one of very few locomotive designers who brought a rigorous scientific method
to their design, and he sought to apply up-to-date knowledge and theories in subjects such as thermodynamics
and gas/fluid flow to the field.
, Loire
, France
on 26 October 1892, and was descended from an English immigrant, one of many who came to France in the 19th Century to teach steel production methods. He achieved a distinction in Mathematics and Science and served as an Artillery Officer during World War I
before returning to the École centrale Paris
in 1919 from which he graduated as Ingenieur des Arts et Manufactures in 1921. He joined the Chemins de fer de Paris à Lyon et à la Méditerranée
(PLM) as a probationer in the Rolling Stock and Motive Power section at Lyon-Mouche depot, but foreseeing poor prospects he left in 1924 and joined the Société Industrielle des Telephones, soon becoming as assistant manager. In 1925 he joined the Chemin de Fer de Paris à Orléans (PO) and, along with Finnish Engineer Kyösti Kylälä
jointly designed the Kylchap
exhaust system. While his principles met with scepticism No. 3566, the first locomotive rebuilt to Chapelon's design was an outstanding success and from 1929 to 1936 several other locomotives were rebuilt to Chapelon's designs.
In 1934, Chapelon was appointed Chevalier of the Legion of Honour
and awarded both the Plumey Prize of the Academie des Sciences and the Gold Medal of the Société d'Encouragement pour l'Industrie Nationale. From 1938 he published the book for which he is most noted La locomotive à vapeur.
photography to watch steam flow.
Before Chapelon, few engineers and designers tried to understand why a certain design worked better than another—they merely worked by trial and error
, trying to replicate the attributes of previous locomotives by rule of thumb, by guesswork, and from empirical theories and design rules that had rarely been given adequate testing.
, and from 1929 on he rebuilt many de Glehn compounds designed by Alfred de Glehn
with his system of compounding. His other major work included optimising the steam circuit, including improving the steam flow by widening steam passages and paths, improving the flow through valve gear, and improved exhaust systems such as his Kylchap
exhaust.
high speed trains.
of Argentina
, and others, and he was accorded the rare honour for a foreign railwayman of having a British Rail Class 86
(electric!) locomotive named for him.
3566 which was released from Tours works in November 1929. As a result of this, three further series of Pacifics were similarly modified.
This was followed by a more comprehensive rebuild of Pacific 4521 as a 4-8-0
which was completed in August 1932. The success of this work led to eleven more rebuilds to locomotives numbered 4701-4712 (later 240 701 - 240 712). These locomotives produced almost 40 ihp continuous per metric ton locomotive weight, which probably still is a world record.
In 1936 Chapelon began the rebuild of a PO 6000 class 2-10-0
as a 2-12-0
with two high-pressure cylinders between the 2nd and 3rd coupled axles mounted behind four low-pressure cylinders. There was also an additional level of "superheat" between the high- and low-pressure cylinders, allowing the loco to achieve a tractive effort of 83700 lb.
The 242 A 1 was perhaps the pinnacle of Chapelon's development of the steam locomotive. The 4-8-4
was a rebuild of Etat 4-8-2
241.101 which retained the 3-cylinder layout, changed it into a 3-cylinder compound system and introducing more of Chapelon's improvements including a triple Kylchap exhaust, double high-pressure valves and Willoteaux valves on the low-pressure cylinders. Completed in 1946 and with a continuous power output of 5500 ihp, the locomotive was rather more powerful than contemporary French electric locomotives, resulting in a hasty redesign of subsequent electric locos, increasing their power by another 1000 hp.
It is considered a matter of enduring sadness that the locomotive was scrapped in 1960, probably as a consequences of French railway authorities not willing to be reminded of Chapelon's superiority in steam locomotive design.
2-8-4
and 4-8-4
locomotives for GELSA (Groupement d'Exportation de Locomotives S.A.) for export to Brazil
. They were highly advanced locomotives with many modern American appliances as well as Chapelon's innovations. André Chapelon was much an admirer of American railroad innovation, even though his work tended to be ignored in the USA.
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...
s. Engineer of Ecole Centrale Paris
École Centrale Paris
École Centrale Paris is a French university-level institution in the field of engineering. It is also known by its original name École centrale des arts et manufactures, or ECP. Founded in 1829, it is one of the oldest and most prestigious engineering schools in France and has the special status...
, he was one of very few locomotive designers who brought a rigorous scientific method
Scientific method
Scientific method refers to a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering empirical and measurable evidence subject to specific principles of...
to their design, and he sought to apply up-to-date knowledge and theories in subjects such as thermodynamics
Thermodynamics
Thermodynamics is a physical science that studies the effects on material bodies, and on radiation in regions of space, of transfer of heat and of work done on or by the bodies or radiation...
and gas/fluid flow to the field.
Life and career
André Xavier Chapelon was born in Saint-Paul-en-CornillonSaint-Paul-en-Cornillon
Saint-Paul-en-Cornillon is a commune in the Loire department in central France.-References:* - Galeries :...
, Loire
Loire
Loire is an administrative department in the east-central part of France occupying the River Loire's upper reaches.-History:Loire was created in 1793 when after just 3½ years the young Rhône-et-Loire department was split into two. This was a response to counter-Revolutionary activities in Lyon...
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
on 26 October 1892, and was descended from an English immigrant, one of many who came to France in the 19th Century to teach steel production methods. He achieved a distinction in Mathematics and Science and served as an Artillery Officer during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
before returning to the École centrale Paris
École Centrale Paris
École Centrale Paris is a French university-level institution in the field of engineering. It is also known by its original name École centrale des arts et manufactures, or ECP. Founded in 1829, it is one of the oldest and most prestigious engineering schools in France and has the special status...
in 1919 from which he graduated as Ingenieur des Arts et Manufactures in 1921. He joined the Chemins de fer de Paris à Lyon et à la Méditerranée
Chemins de fer de Paris à Lyon et à la Méditerranée
The Compagnie des chemins de fer de Paris à Lyon et à la Méditerranée was a French railway company ....
(PLM) as a probationer in the Rolling Stock and Motive Power section at Lyon-Mouche depot, but foreseeing poor prospects he left in 1924 and joined the Société Industrielle des Telephones, soon becoming as assistant manager. In 1925 he joined the Chemin de Fer de Paris à Orléans (PO) and, along with Finnish Engineer Kyösti Kylälä
Kyösti Kylälä
Kyösti Kylälä was a Finnish Railroad engineer and self taught inventor, from Helsinki. In 1919 he patented in the UK an 'Improved means for increasing the draught in steam boilers, especially on locomotives.'...
jointly designed the Kylchap
Kylchap
The Kylchap steam locomotive steam locomotive exhaust system was designed and patented by the famous French steam engineer André Chapelon, using a second-stage nozzle designed by the Finnish engineer Kyösti Kylälä and known as the Kylälä spreader; thus the name KylChap for this design.The Kylchap...
exhaust system. While his principles met with scepticism No. 3566, the first locomotive rebuilt to Chapelon's design was an outstanding success and from 1929 to 1936 several other locomotives were rebuilt to Chapelon's designs.
In 1934, Chapelon was appointed Chevalier of the Legion of Honour
Légion d'honneur
The Legion of Honour, or in full the National Order of the Legion of Honour is a French order established by Napoleon Bonaparte, First Consul of the Consulat which succeeded to the First Republic, on 19 May 1802...
and awarded both the Plumey Prize of the Academie des Sciences and the Gold Medal of the Société d'Encouragement pour l'Industrie Nationale. From 1938 he published the book for which he is most noted La locomotive à vapeur.
Chapelon's methods
He tested his experimental designs thoroughly to understand how they actually behaved, using the most accurate and complete testing and sensing equipment available, such as high-speed stroboscopicStrobe light
A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope...
photography to watch steam flow.
Before Chapelon, few engineers and designers tried to understand why a certain design worked better than another—they merely worked by trial and error
Trial and error
Trial and error, or trial by error, is a general method of problem solving, fixing things, or for obtaining knowledge."Learning doesn't happen from failure itself but rather from analyzing the failure, making a change, and then trying again."...
, trying to replicate the attributes of previous locomotives by rule of thumb, by guesswork, and from empirical theories and design rules that had rarely been given adequate testing.
Efficiency
Efficiency was one of Chapelon's primary concerns in design; some of his locomotives exceeded 12% efficiency, which for a steam locomotive was exceptional. With greater efficiency, Chapelon could achieve greater power in a smaller locomotive that burned less coal, rather than simply enlarging a locomotive for more power.Compounding and steam flow
He was a major proponent of the compound locomotiveCompound locomotive
A compound engine unit is a type of steam engine where steam is expanded in two or more stages.A typical arrangement for a compound engine is that the steam is first expanded in a high-pressure cylinder, then having given up heat and losing pressure, it exhausts directly into one or more larger...
, and from 1929 on he rebuilt many de Glehn compounds designed by Alfred de Glehn
Alfred de Glehn
Alfred George de Glehn was a notable English-born French designer of steam locomotives, and an engineer at the Société Alsacienne de Constructions Mécaniques . His steam engines of the 1890s combined elegance, high speed and efficiency...
with his system of compounding. His other major work included optimising the steam circuit, including improving the steam flow by widening steam passages and paths, improving the flow through valve gear, and improved exhaust systems such as his Kylchap
Kylchap
The Kylchap steam locomotive steam locomotive exhaust system was designed and patented by the famous French steam engineer André Chapelon, using a second-stage nozzle designed by the Finnish engineer Kyösti Kylälä and known as the Kylälä spreader; thus the name KylChap for this design.The Kylchap...
exhaust.
Wheel and rail
Chapelon realised that in order to produce an efficient, powerful locomotive every aspect of it had to be improved and dealt with scientifically. He studied locomotive behaviour at speed and the riding properties of the steel wheel on steel rail; his knowledge was put to use much later on the French TGVTGV
The TGV is France's high-speed rail service, currently operated by SNCF Voyages, the long-distance rail branch of SNCF, the French national rail operator....
high speed trains.
Problems
His curse was that despite his abilities and track record, he never got to design a class of brand-new locomotives that actually got built in any number. He was continually stymied by railway management and politicians, and often his superbly performing locomotives were treated as embarrassments by his superiors—because they showed up the poor performance of the officially approved locomotives!Chapelon's legacy
Chapelon's work lived on in the work of his friend Livio Dante PortaLivio Dante Porta
Livio Dante Porta was an Argentine steam locomotive engineer. He is particularly remembered for his innovative modifications to existing locomotive systems in order to obtain higher performance, energy efficiency and reduced pollution. He developed the Kylpor and Lempor exhaust systems...
of Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, and others, and he was accorded the rare honour for a foreign railwayman of having a British Rail Class 86
British Rail Class 86
The British Rail Class 86 was the standard electric locomotive built during the 1960s, developed as a result of testing with the earlier Classes 81, 82, 83, 84 and 85. One hundred of these locomotives were built from 1965-1966 by either English Electric at Vulcan Foundry, Newton-le-Willows, or...
(electric!) locomotive named for him.
French locomotives
The first locomotive rebuilt to incorporate Chapelon's work was PO 4-6-24-6-2
4-6-2, in the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles , six powered and coupled driving wheels on three axles, and two trailing wheels on one axle .These locomotives are also known as Pacifics...
3566 which was released from Tours works in November 1929. As a result of this, three further series of Pacifics were similarly modified.
This was followed by a more comprehensive rebuild of Pacific 4521 as a 4-8-0
4-8-0
Under the Whyte notation for the classification of steam locomotives, 4-8-0 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and no trailing wheels. The type was nicknamed the Mastodon or Twelve-wheeler in North America....
which was completed in August 1932. The success of this work led to eleven more rebuilds to locomotives numbered 4701-4712 (later 240 701 - 240 712). These locomotives produced almost 40 ihp continuous per metric ton locomotive weight, which probably still is a world record.
In 1936 Chapelon began the rebuild of a PO 6000 class 2-10-0
2-10-0
Under the Whyte notation for the classification of steam locomotives, 2-10-0 represents the wheel arrangement of two leading wheels on one axle, ten powered and coupled driving wheels on five axles, and no trailing wheels...
as a 2-12-0
2-12-0
Under the Whyte notation for the classification of steam locomotives, 2-12-0 represents the wheel arrangement of two leading wheels on one axle , twelve powered and coupled driving wheels on six axles, and no trailing wheels....
with two high-pressure cylinders between the 2nd and 3rd coupled axles mounted behind four low-pressure cylinders. There was also an additional level of "superheat" between the high- and low-pressure cylinders, allowing the loco to achieve a tractive effort of 83700 lb.
The 242 A 1 was perhaps the pinnacle of Chapelon's development of the steam locomotive. The 4-8-4
4-8-4
Under the Whyte notation classification of steam locomotives, 4-8-4 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and four trailing wheels on two axles .Other equivalent classifications are:UIC classification: 2D2...
was a rebuild of Etat 4-8-2
4-8-2
Under the Whyte notation for the classification of steam locomotives, 4-8-2 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and two trailing wheels on one axle...
241.101 which retained the 3-cylinder layout, changed it into a 3-cylinder compound system and introducing more of Chapelon's improvements including a triple Kylchap exhaust, double high-pressure valves and Willoteaux valves on the low-pressure cylinders. Completed in 1946 and with a continuous power output of 5500 ihp, the locomotive was rather more powerful than contemporary French electric locomotives, resulting in a hasty redesign of subsequent electric locos, increasing their power by another 1000 hp.
It is considered a matter of enduring sadness that the locomotive was scrapped in 1960, probably as a consequences of French railway authorities not willing to be reminded of Chapelon's superiority in steam locomotive design.
Exported locomotives
The only locomotives he designed for use outside France were some metre gaugeMetre gauge
Metre gauge refers to narrow gauge railways and tramways with a track gauge of . In some African, American and Asian countries it is the main gauge. In Europe it has been used for local railways in France, Germany, and Belgium, most of which were closed down in mid 20th century. Only in Switzerland...
2-8-4
2-8-4
In the Whyte notation, a 2-8-4 is a railroad steam locomotive that has one unpowered leading axle followed by four powered driving axles and two unpowered trailing axles. This locomotive type is most often referred to as a Berkshire, though the Chesapeake and Ohio Railway used the name Kanawha for...
and 4-8-4
4-8-4
Under the Whyte notation classification of steam locomotives, 4-8-4 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and four trailing wheels on two axles .Other equivalent classifications are:UIC classification: 2D2...
locomotives for GELSA (Groupement d'Exportation de Locomotives S.A.) for export to Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. They were highly advanced locomotives with many modern American appliances as well as Chapelon's innovations. André Chapelon was much an admirer of American railroad innovation, even though his work tended to be ignored in the USA.