Apprenticeship
His apprenticeship was completed in 1906, and he immediately designed a complete car. He managed to convince the local firm of Brazil Straker to hire him, and the design was produced as the successful Shamrock. He remained at Brazil Straker over the following years, and he was particularly influential in convincing company management to take on the repair of various aircraft engines when World War I started. The company's role soon expanded to producing Rolls-Royce Hawk and Falcon engines, as well as major parts of the famous Rolls-Royce Eagle. Henry Royce offered Fedden a senior position with his company, but Fedden declined.
In 1915, Fedden started the design of his own aero engine, along with his draughtsman Leonard Butler. The two were inseparable for the next twenty years, and the part number of most components of Feddens engines were prefixed "FB" to indicate the shared credit. They designed two engines during World War I: the 14-cylinder radial Mercury, notable for the cylinders being arranged helically instead of in two rows, and the larger, more conventional single row nine-cylinder Jupiter design of about 400 hp.
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