Bulleid's Irish "Turf Burner" is often dismissed as a failure alongside his better known Leader Class engines. However Bulleid applied to the Turf Burner the lessons that he learned from his Leader experiments and in consequence it was in almost every respect a very much better machine. It might still be argued that the Turf Burner was a failure since it ran on trial for just a few months in 1957/8 and was ignomineously scrapped some four years later. However Bulleid's experiment failed only because (like Wardale in South Africa 20 years later) the railway authority that paid his fees had by then committed itself to a dieselization program and withdrew its support from his attempt to bring about a steam renaissance.
Of course the machine was experimental and problems were experienced with it. But unlike the Leader, it performed closely to expectations and demonstrated that Bulleid's concept had the potential for success.
On paper, the Turf Burner had a lot going for it. Its rectangular double-ended boiler with a central stoker-fed fan-draughted firebox was more radical than the Leader design, but it overcame the problems experienced with Leader's boiler such as its isolated fireman's cabin and its "superheated" drivers' cabin at the smokebox end. The arrangement of the Turf Burner's boiler/firebox also allowed some novel and clever features to be incorporated, such as a carry-over collector in the fan-driven exhaust system the included gravity return to the firebox stokers.
Fan draughting was adopted in order to reduced particulate (spark) “carry-over” since it produced a uniform (and therefore more gentle) draught instead of the sharp suction peaks generated by exhaust steam draughting. This was necessitated by the light-weight friable nature of the fuel. Fan draughting also provided the advantage of being driver-controllable, enabling boiler output to more closely match the demands made on it.
The two engine units were less radical than Leader's, with piston valves being used in place of sleeve valves. Each engine had two cylinders 12" dia x 14" stroke and was (detachably) mounted on its bogie frame. A compact version of the Bulleid/Walschaerts was specially designed for the locomotive's engines.
The Turf Burner's Co-Co bogies ensured that 100% of its weight was available for adhesion, so wheel slip wasn’t even a consideration given the modest tractive effort available. Chain drive was incorporated similar to that of Leader, but the driving wheels were smaller at only 3ft 7in diameter compared to Leader's 5ft 1in.
Shepherd describes in some detail the several test runs that the Turf Burner undertook. As might be expected from such a novel design, teething problems arose, but unlike Leader, it performed well and demonstrated that the design had potential for improvement. Moreover, and perhaps more importantly, it performed well when burning something akin to solid bio-fuel - and thus the Turf Burner has a potential and important relevance to "modern steam". (See the bio-fuels page of this website.)
The final chapter in Shepherd's book is dedicated to a report on the Turf Burner as prepared by John Click following the 1957/8 trials. Click was a draftsman/engineer who had worked under Bulleid at Eastleigh, and who had assisted him with the design and testing of the Turf Burner. Click recommended several modifications to the prototype that would almost certainly have improved its reliability and its performance. His suggestions were however not implemented because of the railway management's decision to "dieselize" the Irish railways. Shepherd reports that "in conclusion, Click was in no doubt as to the feasibility of a fleet of turf burning steam locomotives operating economically. However only a drastic redesign and redisposition of major components in the prototype could result in the quantity production of machines simple enough to operate and maintain." Click went on to draft up a proposal for a production machine that would have overcome most if not all of the deficiencies in the orginal design.Shepherd provides a valuable history and technical summary of the Turf Burner. However he leaves several aspects of the design inadequately defined: for instance, he provides separate diagrams of the engine and valve gear which fail to show how the two are connected. Furthermore he provides no diagram to explain how the bogies were constructed. It is therefore suggested that his book be read in conjunction with H.V. Bulleid's biography of his father: "Bulleid of the Southern" published by Ian Allan in 1977 - ISBN 0 7110 0689 X.