George Jackson Churchward (31 January 1857 – 19 December 1933) was an English railway engineer, and was chief mechanical engineer of the Great Western Railway (GWR) in the United Kingdom from 1902 to 1922.
Early life Churchward was born at Rowes Farm, Stoke Gabriel, Devon, where his ancestors (the senior line residing at Hill House; his paternal grandfather, Matthew, was the younger son of the head of the family) had been squires since 1457. He was the first son in a family of three sons and two daughters, brothers John (b.1858) and James (b.1860) and sisters Mary (b.1863) and Adelina (b.1870). His father, George Churchward, a farmer, married his cousin, Adelina Mary, daughter of Thomas Churchward, of Paignton, Devon, a corn and cider merchant. He was educated at the King Edward VI Grammar School, contained within the Mansion House on Fore Street, Totnes, Devon. His father's cousin, Frederick Churchward, head of the family, arranged private tuition at Hill House during the school holidays.
Early career
He started his engineering training in 1871 with John Wright, the Locomotive Superintendent of the South Devon, Cornwall and West Cornwall railways, at the Newton Abbot works of the South Devon Railway. While there, he and his fellow pupil Robert Neville-Grenville developed a steam-powered car based on the boiler from a Merryweather fire-engine. When the GWR took over the South Devon Railway in 1876, Churchward had to move to the Swindon Works. In 1877, at the end of his pupilage, he moved to the drawing office, where he worked with "Young Joe" Armstrong to develop a vacuum brake. He was appointed Inspecting Engineer in June 1882, and six months later became assistant to the Carriage Works Manager, James Holden, taking over as Manager on Holden's departure in 1885. Ten years later he became Assistant Works Manager, and soon after Manager, of the locomotive works, and in 1897 became William Dean's Chief Assistant and natural successor. After 5 years as Chief Assistant, during most of which time Dean was ill and delegating much of his design work to Churchward, in 1902 he formally succeeded Dean as Locomotive Superintendent. In 1900 he became the first mayor of Swindon.
Chief Mechanical Engineer
In the 19th and early 20th century, railway companies were fiercely competitive. Speed meant revenue and speed was dependent on engineering. Churchward delivered to the GWR from Swindon a series of class-leading and innovative locomotives. Arguably, from the early 1900s to the 1920s the Great Western's 2-cylinder and 4-cylinder 4-6-0 designs were substantially superior to any class of locomotive of the other British railway companies. On one occasion, the GWR's directors confronted Churchward, and demanded to know why the London and North Western Railway were able to build three 4-6-0 locomotives for the price of two of Churchward's "Stars". Churchward allegedly gave a terse response: "Because one of mine could pull two of their bloody things backwards!" The biggest engineering challenge of the GWR's operations was travelling over the South Devon Banks, a series of steep inclines linking Exeter and Plymouth in Devon, on the GWR's most important route. Although speed was a key competitive driver across the whole GWR route, the South Devon Banks rewarded sure-footed locomotive designs with good adhesion. The largest opportunity to any GWR Chief Mechanical Engineer was the resulting large loading gauge legacy of the GWR's conversion from Brunel's broad gauge track to standard gauge, allowing for wider and higher designs than any of the other later Big Four railway companies.
Philosophy Churchward's design philosophy followed a number of streams of development, for which he thoroughly researched both competitor UK designs, as well as European and North American locomotives. Following principles based on Belgian inventor Alfred Belpaire, Churchward preferred free steaming boilers. This resulted in his use of a Belpaire-style rectangular firebox, which due to its greater surface area for evaporation was less prone to foaming and carry over of water to the cylinders. Churchward inherited from Dean a series of parallel cylindrical boilers, but by applying mathematical principles to the flow of boiler water, quickly improved the flow of steam by adopting tapered boilers, which give their largest area to the point of highest steam production. Churchward then dispensed with the need for a large dome to collect steam, using instead top-feed of water supply from injectors, which together with top-fitted clack boxes hidden within a brass "bonnet" minimised boiler stress. Churchward experimented with compounding, a principle development for marine engines which was widely adopted in European locomotive design. Although through his experimentation Churchward found little difference in operation in terms of the total power developed in compounding locomotives, the use of European locomotives in his trial led to his adoption of higher pressure boilers, and drive power split between two axles on four cylinder designs. His third stream of philosophy was based around piston valves. Churchward's valves were 50% larger than anything seen in the UK to that time, travelled 50% further, and were designed to be concealed. The result gave the minimum loss of pressure as steam passed to the cylinders. Churchward's resulting locomotive designs excluded trailing wheels, which maximised adhesion on the South Devon Banks. He was an early adopter in UK locomotive design of superheating, made efficient through the GWR's exclusive use of the high calorific-value steam coal from the South Wales Coalfield. He also adopted large bearing surfaces to reduce wear, something common in North America. Churchward is credited with introducing to Britain several refinements from American and French steam locomotive practice. Among these were the tapered boiler and the casting of cylinders and saddles together, in halves. His choice of outside cylinders for express locomotives was also not standard in Britain for that time. Many elements of British practice were retained, of course. His locomotives for the most part used British plate frames, and the crew was accommodated in typical British fashion. The selection of a domeless boiler was more common to Britain than to the US.
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