Gallery N°33 : CC Alsthom (C.F.E. period)

Gallery N°34 : CC Alsthom (C.D.E. period)

In March 1963, the year the cc 2400 Alsthom locomotives were ordered, the Railway networks of Africa were very diverse. Most owed their survival to the spreading of diesel power with light and well designed locomotives that preserved a "local " look, while certain mining lines, benefiting from guaranteed heavy traffic, already used engines derived from European networks. The railways were under threat from road traffic, however, with new generations of Berliet , Mercedes and in particular, the logging lorries. It was thought that the future of the railway lay in mass transport and heavy convoys with increased traction capabilities.

But there were limits. OFEROM, who oversaw the cooperation of the networks of the old Empire, were mindful of the four BB 500 locomotives, pulling 1000 ton trains, that struggled to climb the high plateaus of Madagascar, and the "triple traction" of the heavy logging wagons of the Congo-Ocean Railway…
The solution was to substitute the multiple units with a single locomotive of 90 tons, with an engine that produced 2400hp, 18hp per ton. (This was an improvement over the most powerful version of the BB Alsthom locomotives, the series 1100,that produced 2 x 1100 hp for an average weight of 118 tons per double unit, ie, 13.4hp per ton). And why not 20 or even 22hp per ton with the expected development of fast engines of 3000hp? This solution would lead to gains in productivity thanks to fewer axles (6 instead of 8), fewer power units (2 instead of four and with the choice of using a mono-engined bogie C) as well as fewer engine cylinders (12 instead of 2 x 16) etc.

There was an ulterior motive to implementing this clever system. A market already existed (Cameroon, Congo Brazzaville, the Abidjan Niger Railway, Senegal, Cambodia…) and although OFEROM denied it, it was a question of proposing a showcase of the "French style" diesel-electric locomotive, based on model VR 2300 which had been sold to Finland. The CC 2400 suffered as a result of this. The VR 2300 had a light mono-engined bogie C, with two geared, three-phase transmission. They were fast engines and differed from the Sulzer system that had a slower speed. All types were still being tested on SNCF engines..

Following successful trials which were held from April 1965 on the mining line of St Georges de Commiers in La Mure, Isère, four locomotives were ordered. CC2001 arrived on the C.F.E. Railway Network later that year, and had an unusual bi-cab layout which differed from the usual Alsthom design. It was sold off in 1967.

These locomotives, based on the Ethiopian section of the line, quickly monopolised the attention of the maintenance engineers. Being long and heavy they left much to be desired. The bogie had to be kept at reduced speed to avoid derailment. Moreover the three-phase transmission and the type16 PA 4 engine proved difficult to operate, and to maintain with local resources. The power of this engine, already detuned, was further reduced removing any advantage over the BB AD 12 unit which, in case of damage, could at least reach the closest station and keep the line free.
All these locomotives were too sophisticated and did not live up to expectation. Neither did their counterparts in the Congo, Niger, and Zaire…. during the same period. They were all taken out of service prematurely although there were still two locomotives in use in 1987. One of them can still be seen at the little museum at Addis Ababa station where it stands at the head of the Imperial train, which it has had little opportunity to pull.

(Bruno Calvet)