Duke of Gloucester
Resource Type: Image | Posted on 16th March 2012 by Liam Physick
An image from the celebrations of the 175th anniversary of the Liverpool and Manchester Railway, in 2005. The locomotive seen here is BR Standard Class 8 No. 71000 Duke of Gloucester. The Duke of Gloucester was the prototype (hence it was numbered 71000 rather than 71001) for an intended class of Pacific Class locomotives, designed by Robert Riddles, and was built at Crewe in 1954 as a replacement for Princess Royal Class No. 46202 Princess Anne, scrapped after the 1952 Harrow and Wealdstone disaster. Riddles had long argued for the building of such a locomotive, which BR initially rejected on the grounds of cost, but the scrapping of the Princess Anne led to a gap for locomotives with an 8P power classification, for which there was great demand due to their efficient hauling of heavy expresses on the West Coast Main Line. The Duke was based on Standard Class 7, the Britannia Class, with the addition of a Caprotti valve gear (using camshafts and poppet valves rather than piston valves) - one of very few British locomotives to have such a gear. However, the Duke steamed poorly and and consumed fuel heavily, mainly because it used a standard double chimney rather than the Kylchap blastpipe, more suited to the Caprotti system’s fierce exhaust blasts (a Kylchap was recommended by L T Daniels, the representative of the British Caprotti company, while the locomotive was under construction, but the less costly standard chimney had already been installed in the smokebox by then): thus, the choke area of the chimney and blastpipe were both far too small for the pressure creating by the exhaust, leading to poor boiler draughting which meant it had difficulty meeting its timetables. To make matters worse, when the locomotive was restored in the 1970s and 1980s, it was discovered that the ashpan was poorly dimensioned and the dampers too small, thus depriving the fire of air when operating at high speed and leading to inefficient combustion. Crews regarded the Duke as a liability because of its poor steaming. As a result partly of these problems and partly of the Modernisation Plan (the latter factor explained why no attempts were made to improve the Duke), no other locomotives in the Class were built, and it was withdrawn from service in December 1962, after only eight years based at Crewe depot and hauling boat trains on the undemanding North Wales Coast Line between Crewe and Holyhead. Initially, it was earmarked for the National Collection but only its cyliner arrangement was deemed of interest: the left-hand cylinder was displayed at the Science Museum, the right-hand cylinder had already been destroyed. The Duke was then bought by Dai Woodham, owner of Barry scrapyard: though initially it was sent to the wrong place before being retrieved and reallocated to Barry. However, it was rescued in 1973 by the 71000 Duke of Gloucester Steam Locomotive Trust (called the 71000 Preservation Society until 1977) and restored over a period of 13 years: there was much scepticism at the time over whether such a notorious failure could ever amount to anything. The restoration process took so long because many components were missing, including the expensive Caprotti valve gear, and it required sponsorships from industry before the locomotive could be restored as close as possible to as-built condition, though the steel cylinders were replaced by spheroidal iron graphite. It was also modified to remove its design flaws: it was given a Kylchap exhuast system, the chimney was enlarged and the dimensions of the firebox corrected. As a result of these changes, it has finally fulfilled its potential and become one of the most powerful and efficient of all British steam locomotives (it is also more powerful than the Class 40 diesels which replaced it on BR), proving the superiority of its Caprotti valve gear, which provides better exhaust flow and and boiler draughting than the traditional Walschaerts and Stephenson valve gears. Beginning in 1986, it performed flawlessly on the Great Central Railway, and was then brought up to main line standards at Crewe and Didcot, finally getting its chance on a test run between Derby and Sheffield. There it astounded the sceptics, one of them a former fireman (now a driver), Ray Hatton, who had previously said that he would rather go sick than try to raise steam from the Duke if he were allocated to it: in 1995, he insisted on being allowed to drive it in the Shap performance trials, in which the locomotive climbed the notorious Shap bank on the West Coast Main Line, hitting the summit with the highest ever speed attained while hauling a heavy load. It regularly pulls enthusiasts’ special trains. The Duke of Gloucester is probably the only locomotive whose glory days have come in preservation rather than in service: as it bears little mechanical resemblance to its BR days, several other modifications and innovations have been added to see how its performance can be further enhanced, and to speculate on how the Class might have developed had more engines been built. It is seen here alongside the Lord Mayor and Lady Mayoress of Liverpool. In 2005, there were two Lord Mayors of Liverpool: Frank Roderick, who held the post from 2004-5, and Alan Dean, 2005-6.
Categorised under: Landmarks, Landscapes & Locomotives