Class DD2 4-Cylinder
Compound Garratt Goods Locomotive
Designed by Karel Belčamin
Built in 1913 by Beyer, Peacock & Co., Manchester, England
The refusal of the RSR management to authorise construction of the class DD1 Garratt in 1911 was a disappointment to many, not least Karel Belčamin and Beyer Peacock. Belčamin recognised that the DD1 would have been of limited usefulness but was confident that a Garratt goods locomotive of the right type would be of great benefit to the RSR. Some of the class D5 2-8-0s were being rebuilt at this time with larger boilers, which increased their power but upset their weight distribution, so that the lower weight per metre run of the Garratt was seen as a big advantage. In the DD2, the boiler of the DD1 was retained and the running gear augmented by carrying axles at the outer and inner ends of the bogies, ensuring good negotiation of curves at main line running speeds.
It is worth mentioning that Belčamin was quite scathing in his assessment of Garratt engines with carrying axles at the outer ends of the locomotive only, having realised, as many of his contemporaries did not, that the inner ends of the bogies also need adequate guiding on curves. His comment that "they forget there's a bloody hinge in the middle" may well be apocryphal (he had, after all, built a Mallet in 1902 and a Hagans in 1904) but certainly sums up his opinion. When challenged over his DD1 design, which had no carrying axles at all, he pointed out that it was (a) a banking engine for working at low speeds over short distances and (b) not built anyway.
The first of twenty engines was delivered from Manchester in 1913 and allocated to Gunerad shed, from where it underwent exhaustive trials. The RSR was very pleased with its new Garratt and asked Beyer Peacock to accord the follow-up order for 19 further engines the highest possible priority. The entire class had arrived by mid-1914, just avoiding the outbreak of the first world war. The DD2s were used mainly for freight work in the south, where they acquitted themselves admirably, fending off later engines with ease and only succumbing to more modern post-WW2 motive power. The last of these superb engines was withdrawn in 1964.
Text and graphics (C) Norman Clubb 2011