After obtaining his pilot's license in December 1913, he joined the Royal Flying Corps (RFC). He was sent to France and in 1915 was promoted to commander of 16 Squadron. After the Battle of the Somme, Dowding clashed with General Hugh Trenchard, the commander of the RFC, over the need to rest pilots exhausted by non-stop duty. As a result Dowding was sent back to Britain and although promoted to the rank of brigadier-general, saw no more active service during the First World War.
Dowding now joined the recently created Royal Air Force and gained experience in departments of training, supply, development and research. In 1929 he was promoted to Air Vice-Marshal and the following year joined the Air Council. In 1933 Dowding was promoted to Air Marshal and was knighted the following year. In the years prior to World War II he was the commanding officer of the RAF's Fighter Command and oversaw development of the 'Dowding System' -- an integrated air defence system of radar, raid plotting and radio control of aircraft. He also introduced modern aircraft into service such as the eight-gun Spitfire and Hurricane.
In 1940 Dowding, nicknamed "Stuffy" by his men, proved unwilling to sacrifice aircraft and pilots in the attempt to aid Allied troops during the Battle of France. He resisted repeated requests from Winston Churchill to weaken home defence by sending precious squadrons to France. When the Allied resistance collapsed, he worked closely with Air Vice-Marshal Keith Park, the commander of 11 Fighter Group, in organizing cover for the evacuation of the British Expeditionary Force at Dunkirk.
Through the summer of 1940 in the Battle of Britain Dowding's Fighter Command resisted the attacks of the Luftwaffe. "Stuffy" Dowding was credited with winning the battle and was awarded the Knight Grand Cross. However, his prickly temperament and intransigence over issues such as the Big Wing controversy and the inability to counter night raids contributed to his downfall. Air Chief Marshal Charles Portal removed Dowding from his post in November 1940.
Dowding was then sent on special duty in the United States for the Ministry of Aircraft Production, where he made himself unpopular with his outspoken behaviour. On his return he headed a study into economies of RAF manpower before retiring from the Royal Air Force in July, 1942. The following year he was honoured with a baronetcy, First Baron Dowding of Bentley Priory.
In his retirement Dowding became actively interested in spiritualism, both as a writer and speaker. His first book on the subject, Many Mansions, was written in 1943, followed by Lychgate (1945), The Dark Star and God's Magic. Rejecting conventional Christianity he joined the Theosophical Society which advocated belief in reincarnation. He insisted to his friend Lord Beaverbrook that he had been the leader of a Mongol tribe in a previous life. He also espoused the cause of animal welfare. An evangelist with a belief in life after death he wrote in Lychgate of meeting dead 'RAF boys' in his sleep -- spirits who flew fighters from mountain-top runways made of light. One of his former pilots was to comment years later: "at that stage we thought Stuffy had gone a bit ga ga".
Late in life Dowding's belief that he was unjustly treated by the RAF became increasingly bitter. He approved Robert Wright's book Dowding and the Battle of Britain which perpetrated the claim that a conspiracy including Trafford Leigh-Mallory and Douglas Bader had engineered his sacking from Fighter Command. In the wake of the debate that followed, which largely refuted the Wright accusations and showed Dowding's recollections to be at fault, the RAF debated whether or not to make the octogenarian a Marshal of the Royal Air Force, but recommended against it. Dowding saw this as yet another undeserved slight from the service.
Dowding passed on to the great beyond at his home in Tunbridge Wells, Kent, on February 15 1970. At a memorial service at Westminster Abbey, his ashes were laid to rest below the Battle of Britain Memorial Window in the Royal Air Force chapel.
Since his death Dowding has been a popular subject with spiritualists, several of whom have alleged they have contacted him beyond the grave.