Harry Ricardo was born in London in 1885, his grandfather (Alexander Meadows Rendel) was a well known civil engineer. Ricardo’s interest in automobiles started young, when he drove a 3.5hp Benz dog cart aged 13.
He studied Civil Engineering at Trinity College, Cambridge. He was taught by Bertram Hopkinson and also conducted engine research for him. Ricardo’s mix of practical expertise and acute experimental observation gave him a formidable knowledge of subjects such as engine knock and pre-ignition, which were then fairly obscure. In 1908 he founded a business, the Two Stroke Engine Company. The firm exploited Ricardo’s first patented engine, the Dolphin, which was used in fishing boats and automobiles.
The Dolphin was a relatively short-lived venture. By 1914, Ricardo was touring works in America and Europe in preparation for a senior mechanical post in the firm Rendel, Palmer and Tritton. He later became active in promoting new aero engines for the Royal Navy Air Service, leading him to be appointed engineer to the Department of Mechanical Warfare. Consulted on tank development, Ricardo provided new power plant designs of 150hp, later 225hp, for the British Mark 5 tank. Ricardo’s engines were manufactured in large numbers from 1917, transforming the tank into an effective battlefield weapon.
Ricardo was awarded royalties of £30,000 by the government in recognition of his work in tank engine development. He used the money to establish a private centre for research into the internal combustion engine, fulfilling a long-held ambition. Ricardo had formed Engine Patents Limited in 1915 but it was not until 1919 that its base was moved to the Bridge Works at Shoreham. The Ricardo Company was named in 1920.
The firm’s earliest contract was for fuel research for the Asiatic (Shell) Petroleum Company. During the years 191-1921 Ricardo’s compiled an analysis of the quality of commercial fuels to a standard rating – eventually expressed as an ‘octane number’. This was fundamental work. Ricardo’s team of Sir David Pye (1886-1860) FRS and Sir Henry Tizard (1885-1859) FRS eventually became leading British scientists in their own right. Another, more practical consequence of Ricardo’s interest in fuel selection was the enabling of Alcock and Brown’s transatlantic flight in 1919.
The publication of Harry Ricardo’s book The internal combustion engine… (1922-1923) established him as the main authority of the inter-war years. Ricardo’s practical contributions included work on the world’s first diesel passenger car, the Citroen Rosalie, and he enjoyed particular success with the Comet combustion chamber for high-speed diesels from 1931. Ricardo’s interest in aircraft engines continued and his association with the competing Bristol, Napier and Rolls-Royce companies testify to his unique role in commercial research.
In championing the sleeve valve aeronautical engine during the Second World War, Ricardo remained a true piston-engineer. This was despite his assistance to Sir Frank Whittle’s development of the jet engine, for which he designed a barometric fuel control system. The jet would eventually consume Ricardo’s own wartime high performance type, the revolutionary Rolls Royce Crecy engine, tested in 1944 but never flown.
In 1948, Harry Ricardo was knighted. He had earlier been elected a Fellow of the Royal Society (1929) and had served as President of the Institution of Mechanical Engineers (1944-1945). Post-war, the Ricardo Company increasingly moved into automotive and commercial vehicle engine research, but also carried out pioneering research in other areas. For example, British Railways’ foray into diesel-mechanical Fell locomotives, developed in 1948-1951, utilized Paxman-Ricardo prime movers and expertise.
Harry Ricardo retired fully in 1965. Before his death in 1974 he wrote a full account of his life and times, Memories and machines (1968), an entertaining testimony of what it is to be an engineer.