Sir John Edward Thornycroft, KBE (1872–1960) was a British mechanical and civil engineer. He worked for the family business of John I. Thornycroft & Company, a shipbuilder to the Royal Navy and others. He played a key role in the early development of destroyers and helped the business to branch into land-based transport as managing director from 1906. During the First World War Thornycroft developed the first coastal motor torpedo boats and launching systems for depth charges and was knighted for his work. He also played a key role in the Second World War, making technical decisions on warship armament. Shortly before his death his son, John Ward Thornycroft succeeded him as chairman and managing director of the company.
