An Irishman, Dermot Boyle was the first RAF officer who had not fought in the First World War to become CAS, and also the first to have been trained at the RAF College, Cranwell. Lord Trenchard, its founder, had always looked forward to the day when a former cadet would reach the highest position the service had to offer and none was more delighted than he when Boyle was appointed. Sadly, the new CAS's first engagement was to attend the great man's funeral.
Boyle's early service saw him flying operationally in Iraq and then, as a qualified flying instructor, demonstrating his exceptional pilot skills in display flying at Hendon and elsewhere. In the 1930s he served with the Auxiliary Air Force, gained staff experience, and as war approached returned to Cranwell as Chief Flying Instructor. The wartime years found him first in France with the Advanced Air Striking Force and then in Bomber Command, where he commanded a Hampden squadron and later RAF Stradishall, in Suffolk. A spell in the Cabinet Office Secretariat in 1941 gave him an invaluable insight into the higher realms of policy-making, and from 1943 to 1945 he held a key operational appointment as Senior Air Staff Officer in 83 Group, one of the tactical formations specially set up for the invasion of north-west Europe.
Six years later he was back in operational command, this time as Air Officer Commanding No 1 Group in Bomber Command, where his primary task was to see the RAF's first jet bomber, the Canberra, into squadron service - a wonderful aircraft, he called it, and he often flew it himself, most notably in 1952 when he led a flight on a 24,000-mile tour of South America. Then he moved on to become C-in-C Fighter Command, where he oversaw the introduction of another of the RAF's great post-war aircraft, the Hunter.
Boyle took over as CAS from Sir William Dickson on 1 January 1956 and soon became embroiled in the mounting crisis that followed Egypt's nationalisation of the Suez Canal. Inevitably the various stages of military planning and preparations, compounded by the political uncertainties, occupied much of his time and that of his fellow chiefs of staff, but Boyle himself refused to become involved in the politics. He knew nothing of the Israeli connections, though he certainly shared his colleagues' misgivings about a situation in which Anthony Eden was being steadily overwhelmed. His task was simply to ensure that the RAF could do what was required of it, and he shared the credit for the success of the air offensive in Operation Musketeer, carried out by the RAF in co-operation with the Fleet Air Arm and the French Air Force.
The Defence Review presented problems of a different order. This complete reassessment of British defence policy had started in early 1956, its cause the government's conviction that Britain's economic performance had to be improved and that large savings in expenditure on conventional forces were essential to that end. After Suez the painful process was resumed, this time under a new Minister of Defence, Duncan Sandys, and the Defence White Paper of April 1957 caused consternation around the RAF. Admittedly Boyle applauded one key aspect, the confirmation of the role of the V-bomber force in providing the United Kingdom's nuclear deterrent, in which he was a passionate believer. The rest of Sandys's ideas, however, were anathema, and having decided that resignation would serve no purpose Boyle resolved to fight.
While he had no choice but to accept heavy cuts, especially in Fighter Command and Germany, Boyle found many influential friends, notably in the Army and also in politics, willing to support him, and, as he himself put it later, the fabric of the RAF as a whole was preserved. Moreover - a notable achievement - he persuaded Sandys to agree to the development of the RAF's new strike and reconnaissance aircraft, the TSR2. At the same time he realised the importance of countering the effects of the adverse publicity both within and outside the RAF, and by repeatedly proclaiming his own belief in the future of the manned aircraft he made a considerable personal contribution to the national debate. For those in the RAF, increasingly wondering about their prospects, his was a timely demonstration of inspired leadership.
Many other matters, too, engaged Boyle's attention, including an attempt by the Navy, strongly encouraged by Mountbatten when he became Chief of the Defence Staff, to take over the aircraft of Coastal Command, and a full-scale study of the future roles of air transport. In the nuclear field there were the successful tests of the British hydrogen bomb at Christmas Island; the agreement to the deployment of the Thor missile in the United Kingdom - a decision which Boyle supported since it brought the RAF into a new field of technology and would help prepare for the advent of Britain's intercontinental ballistic missile, Blue Streak; and the growing question about Blue Streak itself, coupled with the possible acquisition of the air- launched Skybolt in its place. When Boyle handed over to Sir Thomas Pike at the end of 1959 there remained many unsolved questions but the RAF was in much better heart than at one stage had seemed possible.
He was now aged 55 and new challenges lay ahead, both in industry and in continuing connections with the RAF. As Vice- Chairman of the British Aircraft Corporation from 1962 to 1971 his service experience was invaluable for many of the new aircraft projects; the cancellations, especially that of the TSR2, horrified him, but other projects such as the MRCA, the future Tornado, held great hopes for the future. He also found time for a new scheme very close to his own heart, namely the establishment of the RAF's own museum at Hendon; as the first chairman of its board of trustees from 1965 to 1974 he provided much of the inspiration for this widely admired RAF institution. The RAF Benevolent Fund, of which he was Deputy Chairman, and the RAF Club, of which he was president, also owed him much, and to the end he showed an interest in the modern RAF.
Dermot Boyle will be remembered as one of the great father-figures of the RAF. Superb flying ability, great staff skills, inspiring leadership, dominating presence, power to hold an audience, charm, kindliness: such qualities combined to make him one of the most respected and best loved of all the RAF's high commanders.