Four out of five fatal aircraft accidents are due to human error. Three out of five are due to pilot error. This book examines technical aspects of the problem from the viewpoint of one of the UK's most experienced aviation cardiologists. Upon a Trailing Edge is Michael Joy's story of a life spent in aviation and cardiology. His narrative spans the end of the Second World War to teaching on behalf of the International Civil Aviation Organisation, worldwide. It includes some history of powered flight, experience in the cadet force in the 1950s, learning to fly a Tiger Moth on an RAF scholarship, training as a doctor - later a cardiologist, and the ownership of various aircraft. Also flying the Concorde. Drawing on his personal aviation experience, the author examines the loss in 1972 of the HS Trident aircraft - G-ARPI, 150 seconds after take-off. There were handling issues and the pilot-in-command had suffered a heart attack. As a result of this accident he was appointed cardiologist to the UK Civil Aviation Authority where he remained as a consultant for the next 38 years. He helped evolve a scientific approach to medical fitness determination and co-drafted the European and International fitness standards in the speciality. Human error, risk and aviation accident causation are introduced in the context various fatal hull losses. Upon a Trailing Edge visits many countries and unusual places including the Khyber Pass, the jungle aircraft factory in Bandung, and the slave island of Goree. It will appeal to readers interested in the development of aviation safety, and travel - both as pilot-in-command in Europe, and further afield.