Professor John Eirwyn Ffowcs Williams FREng: Engineer, educator, researcher and entrepreneur, Cambridge Professor and Master of Emmanuel College 25 May 1935–12 December 2020.

I first met Shôn in October 1973. I had just started Part III of the Cambridge Mathematical Tripos – a post-graduate course that was retrospectively awarded a Masters' Degree in Mathematics. After a summer job working with Ted Broadbent on aircraft noise at the Royal Aircraft Establishment in Farnborough, I had decided do a PhD in Aeroacoustics. I asked Sir James Lighthill for advice and he told me that he was now focused on biomechanics but a new professor had recently arrived in the Cambridge Department of Engineering and that I should ask him. I made contact with Shôn, saw him in his office that afternoon, and he agreed to supervise me for a PhD. As quickly and simply as that, I was on a path that for me was transformational, not only an exciting research future, but the start of my transition from mathematics into engineering. Throughout my career, Shôn continued to be a major influence on me as he has for many others. [ABSTRACT FROM AUTHOR]