provided diesel engines for automotive, railway, industrial, earth-moving and marine use. Sentinel (Shrewsbury) Limited was bought in 1956. Sentinel made machine tools and industrial locomotives. Rolls-Royce took over Sentinel's Shrewsbury factory for diesel engine production and all its diesel work was transferred there. West Riding manufacturer of diesel shunting locomotives, Thomas Hill (Rotherham) Limited, was added to the group in 1963. In 1973, when Shrewsbury activities were put under the umbrella of new owner, Rolls-Royce Motors, the range of diesel engines included: C range: 4, 6, and 8 cylinder engines with power output from 100 to 450 bhp. Used in generating sets, compressors etc., construction equipment, railway and other industrial purposes and marine propulsion. Eagle: a modified version of the C range 6-cylinder engine named Eagle is used in heavy vehicles, their output 200 to 300 bhp. D range: V engines with outputs from 400 to 750 bhp for generating sets, marine and railway applications. Aero-engines In 1907, Charles Rolls, whose interests had turned increasingly to flying, tried unsuccessfully to persuade Royce and the other directors to design an aero engine. When World War I broke out in August 1914, Rolls-Royce (and many others) were taken by surprise. As a manufacturer of luxury cars, Rolls-Royce was immediately vulnerable, and Claude Johnson thought the bank would withdraw its overdraft facility on which Rolls-Royce depended at that time. Nevertheless, believing that war was likely to be short-lived the directors initially decided not to seek government work making aero engines. However, this position was quickly reversed and Rolls-Royce was persuaded by the War Office to manufacture fifty air-cooled V8 engines under licence from Renault. Meanwhile, the Royal Aircraft Factory asked Rolls-Royce to design a new engine. Despite initial reluctance, they agreed, and during 1915, developed Rolls-Royce's first aero engine, the twelve-cylinder Eagle. This was quickly followed by the smaller six-cylinder Hawk, the Falcon and, just before the end of the war, the larger Condor. Throughout World War I, Rolls-Royce struggled to build aero engines in the quantities required by the War Office. However, with the exception of Brazil Straker in Bristol Rolls-Royce resisted pressure to license production to other manufacturers, fearing that the engines' much admired quality and reliability would risk being compromised. Instead the Derby factory was extended to enable Rolls-Royce to increase its own production rates. By the late 1920s, aero engines made up most of Rolls-Royce's business. Henry Royce's last