He was born in 1873, the son of Captain Montague Trenchard, of the King's Own Yorkshire Light Infantry. He was educated privately, and after several failures in examination entered the army by way of the militia, receiving his commission as a second lieutenant in the Royal Scots Fusiliers. After some years in India he served in the South African War, at first with the Imperial Yeomanry Bushman Corps, and later with the Canadian Scouts. During the operations west of Pretoria, in the autumn of 1900, he was dangerously wounded, but served again, during the concluding years of the war, with the mounted infantry in the Transvaal, the Orange River Colony, and the Cape Colony. There followed a period of distinguished service in Nigeria, and then he was at home for a time. In February 1912, three months before the Royal Flying Corps came into being, he applied for employment with the mounted branch of the Colonial Defence Forces, in Australia, or New Zealand, or South Africa. In May he applied for employment with the Macedonian Gendarmerie. These applications were noted for consideration at the War Office; in the meantime his mind turned to the newly-formed Flying Corps. Mr. T. O. M. Sopwith tells the story of how he learned to fly.
'Major Trenchard (as he was then) arrived at my School at Brooklands one morning in August 1912. He told me that the War Office had given him ten days in which to learn to fly and pass his tests for an aviator's certificate, adding that if he could not pass by that date he would be over age. It was no easy performance to undertake, but Major Trenchard tackled it with a wonderful spirit. He was out at dawn every morning, and only too keen to do anything to expedite tuition. He passed in about one week from first going into the air as a passenger. He was a model pupil from whom many younger men should have taken a lead.'
On the 13th of August 1912 he took his certificate, flying a Farman machine. Then he went to the Central Flying School, where he took the necessary courses and passed the necessary examination. On the 1st of October he was appointed instructor on the staff of the school. These were arduous times; an efficient British air force was yet to make, and the political horizon was even more threatening than it was a year later. He continued at this work till the 23rd of September 1913, when he was appointed assistant commandant to Captain Godfrey Paine, a post which he held up to the outbreak of war. By that time a very large proportion of the officers of the Flying Corps had passed through his hands. His policy was the policy of Thorough. He played his part in producing the efficiency of the original Flying Corps.
On the 7th of August 1914 he was appointed Officer Commanding the Royal Flying Corps (Military Wing), with the temporary rank of lieutenant-colonel. The headquarters, the aircraft park, and the four squadrons left for France at once. Mr. G. B. Cockburn at that time was at Farnborough, where, from April onwards, he had held an appointment in the Aeronautical Inspection Department. He has kindly contributed a note:
'The squadrons hurried off to the front,' he says, and in a short time there remained practically nothing in the way of machines or pilots in the country. Colonel Trenchard took charge to create something out of nothing. His presence at Farnborough had a most enlivening effect on every one who came in touch with him, and as I had to pass through to him all the machines issued in those days, it was my good fortune to have very close observation of those methods which have led to his great success.'
In his attempt to create something out of nothing he had the whole-hearted support and help of the small but admirably efficient aeronautical department of the War Office, directed for the time by Colonel Brancker. One great strength of military aviation in its early days was that it attracted into its service, by natural magnetism, men of an adventurous disposition. The dangers of the Flying Corps, rather than the good pay that it offered, brought to it recruits strong in all the virtues of the pioneer. No one who covets a life of routine, with defined duties and limited liabilities, ever yet took up with aviation as a profession. The men who explored and took possession of the air in the twentieth century are the inheritors of the men who explored and took possession of America in the sixteenth century. It is one of our chief title-deeds as a nation that adventurers are very numerous among us. We were not the first to show the way, in either case, but because we are a breeding-ground of adventurers we are richer than other nations in the required type of character, and we soon outgo them. When the war came there was a long list of officers and men who were seeking admission to the Flying Corps—the best of them as good as could be found in the world. The very staff of the directorate at the War Office had the same quality. They were men of spirit and initiative, not easily to be bound by red tape. A short account of Colonel Brancker, who was Colonel Trenchard's main support, will illustrate this special good fortune of the Flying Corps.
Major-General Sir William Sefton Brancker, as he now is, began his soldiering in the Royal Artillery. He saw much active service in the South African War, and thereafter was chosen for staff service in India. His opportunity came in the winter of 1910. In that year the British and Colonial Aeroplane Company, in order to demonstrate the new art to the General Staff in India, sent out to Calcutta an expedition consisting of a manager, the French pilot Monsieur H. Jullerot, two British mechanics, and three Bristol box-kites fitted with 50 horse-power Gnome engines. Captain Brancker, as Quartermaster-General of the Presidency Brigade, was responsible for the disembarkation of the party. What he had already heard of flying had excited his keen interest; he attached himself firmly to the expedition, and was permitted to fly, unofficially, in the character of observer. The first aeroplane was erected on the Calcutta racecourse, and flew in the presence of a huge crowd of spectators.
There were cavalry manœuvres that year in the Deccan, and General Rimington, who was organizing them, set aside a part of his manœuvre grant to enable Captain Brancker to bring an aeroplane and take part in them. The aeroplane arrived at Aurangabad early in January 1911, and was hastily erected under a tree by the two mechanics, assisted by six willing and jocular privates of the Dublin Fusiliers. It was ready forty-eight hours after detrainment, just in the nick of time. The first flight was made by M. Jullerot and Captain Brancker, the day before the manœuvres began, in the presence of twelve generals, one of whom was Sir Douglas Haig, at that time Chief of the Staff in India, and a numerous company of staff officers. Next morning the aeroplane was attached to the northern force at Aurangabad, whose task was to drive back the rearguard of a southern force retreating towards Jalna. Captain Brancker and M. Jullerot made a flight of about twenty-seven miles at a height of 1,100 feet, and the hostile rearguard was accurately located. A full report was in the hands of the commander of the northern force in less than an hour and a half from the time of his demand for information.
Subsequent flights were less successful; indeed, the next morning the aeroplane crashed from a height of a hundred feet; the two aviators escaped with a few scratches, but the machine was reduced to matchwood. Nevertheless, the first thorough performance by a military aeroplane of a really practical military mission deeply impressed General Sir O'Moore Creagh, the then Commander-in-Chief, and, had it not been for lack of money, he would have started a flying organization in India a year before the Flying Corps in England came into being.
Not long after his return to England, Major Brancker was employed at the War Office under General Henderson. As soon as the opportunity presented itself, he learned to fly. He took the short course at the Central Flying School and was appointed to the Royal Flying Corps Reserve. In October 1913 he succeeded Captain Ellington on the staff of the Military Aeronautics Directorate. He continued to fly. The first really stable aeroplane, the B.E. 2c, was produced in June 1914; and Major Brancker, who describes himself as 'a very moderate pilot', flew the first of the type from Farnborough to Upavon, without the use of his hands except to throttle back the engine before alighting; during the flight he wrote a full reconnaissance report.