The 4-8-2 wheel arrangement - 241 in French parlance, which counts axles rather than wheels - represented the largest regular-production passenger locomotives ever to serve in France. The first of the type were 41 engines of class 241A, built starting in 1925 for the Chemins de Fer de l'Est (Eastern Railway), which ran due east from Paris to cities such as Nancy and Strasbourg.
Like most French express engines, the 241A was a de Glehn compound, a design that would seem frighteningly complex to engineers or shop crews anywhere outside of France. To make more efficient use of steam, a compound engine uses steam twice. Boiler steam is fed to high-pressure cylinders and then exhausted into one or two larger, low-pressure cylinders to work again before going up the stack. Following in the footsteps of their countryman Anatole Mallet, one of the earliest advocates of compounding, Alfred de Glehn and Gaston du Bousquet at the end of the nineteenth century designed a four-cylinder compound system, with high-pressure cylinders outside the frames and low-pressure cylinders inside the frames.
The chauffeur of a de Glehn compound had five working possibilities: normal compounding; four-cylinder simple operation for starting (high-pressure boiler steam to all cylinders); compounding with some additional high-pressure steam to the low-pressure cylinders, for extra power on hills; and high-pressure steam to only the low-pressure or only the high-pressure cylinders, to limp home in case of mechanical failure. All of this was controlled by two throttles (one for each pair of cylinders), two reverse levers, and an intercepting valve to manage the flow of steam from high-pressure to low-pressure cylinders. In the 241A, an additional task was controlling the six-jet blast-pipe in the smokebox, which varied the firebox draft. In most countries, shop crews would have declared the de Glehn system a maintenance nightmare and engineers would have found it horribly complicated. But French shop crews appeared to thrive on its complexity. And French chauffeurs, trained as mchaniciens (engine mechanics) rather than firemen as in other countries, prided themselves on the throttle artistry needed to achieve the wonderful performance that a de Glehn compound could deliver.
The original 241As worked well enough that 49 more were ordered for the Chemins de Fer de l'tat (State Railways). A series of trials in 1933, however, showed the 241A was inferior to the smaller, famous Pacifics of the Paris-Orleans Railway, as rebuilt by Andr Chapelon, "the genius of French steam." As a result, the 241As - like several other classes of French steamers - were rebuilt along Chapelon lines, resulting in a 40% increase in horsepower with a 15% decrease in coal consumption. The rebuilt engines served the Est, Etat, and later the nationalized French railways (SNCF) into the 1960s. At least two are preserved: the prototype, No. 241A1, in the Cit du Train in Mulhouse, France, and 241A65, the largest hand-fired, operating steam engine in Europe (which barnstormed across Switzerland this past summer, doubleheading with postwar French steamer 241P17). New for 2010, M.T.H. introduces our superdetailed model of this premier French steamer - complete with French passenger station announcements and crew talk, and authentic French whistle - as it appeared in Era II after Chapelon had worked his magic.