Professor Ronald Milne took up the Chair and Headship of the Department of Theoretical Mechanics (later renamed Engineering Mathematics) in the Engineering Faculty in 1971. He immediately set a tone for his Department by taking on major first-year teaching responsibilities, which he saw as a duty of a head of department. On the research front, he encouraged staff to pursue their own enthusiasms and interests. As a result the Department had a particularly diverse research profile. Ronald led the planning and implementation of the new degree course in Engineering Mathematics, introduced in 1977. He was appointed Dean of Engineering for the years 1980-83, a period which involved him at a high level in the shaping of the University’s response to the unprecedented and extremely severe cuts imposed on the UK university system by the Thatcher government. It was widely felt by his colleagues that Ronald handled his involvement in this unhappy task with great skill, impartiality and sound judgement.

Ronald Douglas Milne was born in 1930 in Aberdeen where his father ran a family engineering business. He attended Aberdeen Grammar School and from there, in 1948, went to Aberdeen University to read Civil Engineering, graduating with First Class Honours in 1952. He continued his studies at Cranfield College of Aeronautics, gaining an MSc with Distinction in Aeronautical Sciences in 1954. In vacation periods, before and during his time at Cranfield, Ronald worked at Fairey Aviation at Hayes, Middlesex. After graduating, he joined English Electric Guided Weapons Division at Stevenage.

In 1956, encouraged by his former Professor at Cranfield, Alec Young FRS, Ronald joined Queen Mary College, London as a lecturer, where Alec was Head of Aeronautical Engineering. He completed his PhD on the Dynamics of the Deformable Aeroplane in 1962 and was promoted to Reader in 1964. During his time at QMC, he made some remarkable contributions to aeronautics: he developed a unified mathematical framework for aeroelasticity, published in a series of papers and the milestone report 'Dynamics of the Deformable Aeroplane' (Aeronautical Research Council R&M 3345, 1964). With this work, he built a bridge between flutter analysis and rigid body flight mechanics, which was of particular importance at the time for the Concorde designers. Ronald undoubtedly possessed a special ability to express engineering problems using rigorous mathematical principles which he could then use as a starting point for finding well bounded approximate solutions. He subsequently wrote a book, Applied Functional Analysis (Pitman, 1980), in which he drew examples using a general and elegant finite element theory for continuum mechanics. 

After his period as Dean of Engineering, Ronald returned to departmental duties and developed new research directions, making advances in understanding the mechanics of the golf swing, allowing him to combine his professional and sporting interests in a unique fashion. During the late 1980s he also worked closely with Alan Simpson (Aeronautical Engineering), and staff at the Royal Aircraft Establishment, Bedford to develop a rigorous treatment of the strain pattern analysis method for re-constructing the deformation of helicopter blades in flight using measured structural modes, and publishing a definitive assessment of its merits. Ronald took early retirement in 1989, but continued to lecture part-time and to research the golf swing, both theoretically and in practice on local golf courses, well into retirement.

Ronald Milne touched the lives, and inspired the careers, of many student engineers who were fortunate to come under his wing. He is one of the unsung heroes of his profession, seeking neither fame nor glory as he created exciting and innovative tools for dealing with complex engineering problems. 

Ronald married Janet Dorothy Davidson in 1955. They were a devoted and hospitable couple, who created a kindly social atmosphere within his Department at Bristol. Ronald died peacefully after a long illness and is survived by Dorothy, his daughter Alisoun, son Douglas and three grandchildren.