A hot air engine was based on a device by which English engineer and aeronautical legend?
Hot air engine A hot air engine (historically called an air engine or caloric engine) is any heat engine that uses the expansion and contraction of air under the influence of a temperature change to convert thermal energy into mechanical work. These engines may be based on a number of thermodynamic cycles encompassing both open cycle devices such as those of Sir George Cayley and John Ericsson and the closed cycle engine of Robert Stirling. Hot air engines are distinct from the better known internal combustion based engine and steam engine.
Frank Barnwell Captain Frank Sowter Barnwell OBE AFC FRAeS BSc (1880 – 2 August 1938) was a British aeronautical engineer. With his elder brother Harold he built the first successful powered aircraft made in Scotland and later went on to a career as an aircraft designer with the Bristol Aeroplane Company, designing aircraft such as the Bristol Fighter, the Bulldog and the Blenheim.