Standard Class 6 'Clan' pacifics

‘Clan Pacific’


The BR Standardization program following nationalization was highly controversial to say the least. Many people who hailed from the GWR, Southern or LNER were unhappy with the level of LMS influence on all the new types and the ignoring of the designs of the engineers Bullied, Peppercorn and Hawksworth, particularly as the latter two had only had the job of locomotive superintendent for a few years. Indeed, despite the success of Bullied’s pacifics, Peppercorn’s three designs and Hawksworth’s ‘Modified Halls’, these were overshadowed by the supposedly more modern and less complex tanks and tender moguls of Ivatt on the LMS. The fact was that the complex oil-driven chain baths of Bullied’s Pacifics, the LNER complex 3-cylinder designs, and the lack of innovation in GWR practice were unattractive for a standard, all-routes design theory.

However, BR did not follow its own standardization practice, that is no building of superfluous locomotives or experimentation. An example of this was the prevention of Riddles building the Standard 8P Pacific design (a more powerful version of the ‘Britannias’) due to the large number of ex-LMS/LNER pacifics operating, even though many of these were either worn out and in need of repair work, or machines that did not fit in with the ‘ease-of-maintenance’ Standardization program (case in point: Gresley’s 3-cylinder pacifics, whose 3rd-cylinder with its conjugated valve gear was complex and required careful attention. Also, the Railway Executive was also biased against 3-cylinder designs which shows up in the fact that all but one Standard class had two cylinders.). The sole member of the class was constructed only after the Princess Coronation-class pacific, Princess Anne, was destroyed in the terrible triple collision at Harrow and Wealdstone. (The resulting engine, Duke of Gloucester, was doomed thanks to errors made in construction, among them the fitting of a normal chimney compared to the preferred Klychap exhaust. A poor performer in BR service, it was happily rescued from the scrap-head by preservationists who during rebuilding corrected the errors made. The result was one of the finest express locomotives ever seen, and still a great performer on heritage main-line services).

Despite the lack of tolerance towards mavericks, BR still gave permission for Riddles to construct just ten members of the smaller version of the ‘Britannias’ for service on lighter branch lines along wider route availability. The new design: christened the Standard Class 6 Light pacific, was given the more commonly known title of ‘Clan’ Pacific.

Considering the emphasis on ‘economy’ by British Railways for its new designs, it seems a strange decision to make such a small number which did not match the other designs and would hence cause bottlenecks in part availability. This can be partially explained; originally 25 locomotives were planned, however due to the shortage of steel in Britain at the time the second batch of fifteen were continually postponed until they were cancelled in the wake of the infamous ‘Modernisation Plan’ of 1955. (Co-incidentally, there was a second superfluous group of engines was constructed that BR would have been better off either expanding or leaving alone: the BR standard class 3 2-6-0, of which only 20 were built). The small number of locomotives prevented effective training of personnel, which led to problems when a ‘Clan’ was sent to areas other than where the enginemen and support crews were familiar with them. (It must be added that many locomotive crews had a bias against the new ‘standards’ which replaced their old types from the ‘Big Four’, especially those crews who were from the GWR/LNER/Southern since the standards had an overwhelming LMS influence to them).

To make matters worse the design was not given time for its various bugs and defects to be worked out, due to the demand for a light pacific on the main lines in the West of Scotland. The main problem, which would have been ironed out if Riddles had been given the chance to modify the design (this was prevented by the Modernisation Plan of 1955, once again), was the fitting of a blast pipe too small to allow good airflow, and a single chimney rather than a double. Many drivers complained of a lack of pulling power, which can partially be explained by the unfamiliarity of many crews with the type, but certainly the rushed construction was mostly to blame.

Despite these problems, the ‘Clans’ could be excellent machines when handled properly, and were found useful when used in areas such as the Midlands and on heavy Scottish boat trains. The class even holds a record that is very unique: a member of the type was the only ‘pacific’ locomotive to ever run on the West Highland Line, in a successful test to see if a 4-6-2 could manage the tightly graded/curving line. They were also tried in services on the eastern region until dieselization forced them into secondary duties. However, their reputation was tarnished by an error which accidentally had them working heavier Class 7P duties (which they were unable to keep to due to their lower 6P rating) which caused missed timetables and a shift of 7P/8P pacifics to replace them there.

Like the other BR standards, the type had hopelessly un-economic lives, the oldest surviving a mere 14 years, all being scrapped by 1966. The second batch had been cancelled well before, but part of the frames for the first of the new 15, to be named ‘Hengist’ had been completed but stopped due to the steel shortage.

The class has never lost its reputation of being a failure even though it did have many successes, probably stemming from the multitude of complaints received about the many troubles. There is little doubt however that the construction of a mere 10 engines was a tremendous waste of development money given that they were never multiplied upon and were not modified to give better service as Riddles intended. However, the ‘Clans’ were easy to maintain, all-purpose given their lighter weight and smaller size and excellent performers when treated with care. Overall, they can be classed as a success, but were not without their problems.

Although none of the class survived, thanks to the miracle of ‘new-build’ projects, what would have been the first of the next batch of 15 engines is well underway at the East Somerset Railway. Depending on whether it beats the new-build Standard Class 3 2-6-2T into service, ‘Hengist’ will be the 1000 steam locomotive to be built to a BR standard design. More importantly, given the modifications that will be added to bring the class up to Riddles’ original intentions, the ‘Clan’ pacific may well undergo a redemption in reputation not unlike that of the similarly maligned Duke of Gloucester.