British military aviation has its roots in the Royal Engineers, which established a balloon corps in 1908. In May 1912, the Royal Flying Corps was established with a military wing, which worked for the army; a naval wing for operations with the fleet; the Central Flying School for instructional purposes; a repair depot called the Royal Aircraft Factory; and a reserve.
A form of interservice rivalry developed almost at once between the military and naval wings, and shortly before the declaration of war, in the summer of 1914, the naval wing broke away to become the Royal Naval Air Service.
When war was declared, the RFC deployed with the British Expeditionary Force; an aircraft park and four squadrons (Nos. 2, 3, 4, and 5), each equipped with the entire mixed bag of aircraft then in the British inventory. After a series of moves necessitated by the initial British retreat, headquarters in France was established at Saint Omer, where it remained for most of the war. The first field commander of the RFC was Brigadier General David Henderson. Henderson would shortly return to England, though, leaving command in the field to Hugh Montague 'Boom' Trenchard.
Initially, each RFC unit acted as something of a self-contained air force, performing the complete range of activities, which at the time consisted primarily of reconnaissance duties with the occasional bombing mission. As the war progressed, the force grew in number, and by 1916 squadrons began to specialize either as fighter, bombing, or reconnaissance units, the latter role being further divided into photographic and artillery functions. As a consequence of specialization, the practice of units having a multiplicity of types was abandoned, and squadrons started to become known not only by their role but also by what type of equipment they possessed. Balloon companies using tethered observation balloons as artillery spotters began appearing in British service in 1915 and remained a fixture on the Western Front throughout the war.
Technological advances were rapid during the war, and keeping up with the enemy in the design and deployment of new types was a constant problem. The British sometimes suffered severely as a result. When the Germans were first to develop an interrupter gear -- allowing a machine gun to fire through the propeller arc -- the RFC found itself on the receiving end of the 'Fokker scourge.' During the spring of 1917 the problem reached a crisis. During the Battle of the Somme, the previous autumn, the Luftstreitkräfte (Air Service) had organized its single-seat fighter force into heterogeneous jagdstaffeln (fighter squadrons) and reequipped with the Albatros D.I and D.II. The type had been refined over the winter into the D.III.
The RFC, however, had lagged in the introduction of new types and went into the spring with the same complement of tired aircraft,mostly BE 2s that had been in use for the last two years. It paid a high price – the highest number of casualties in a single month it would suffer during its existence – a month that went down in history as 'bloody April.'
Technological advantage was not the only factor in these losses; doctrine also played a part. Throughout the war, Trenchard followed an offensive policy. This action has attracted its share of criticism, but faced with German occupation of the high ground and the insatiable intelligence needs of the army, often only satisfied by aerial reconnaissance, the RFC seems to have had little choice but to press on with what it had.
The situation improved over the summer of 1917 with the introduction of the Sopwith Camel, the SE 5/5a, the de Havilland D.H. 4, and the Bristol Fighter; the SE 5/5a was the best design to emerge from the Royal Aircraft Factory during the war, the other three, of course, being the products of private firms. From that point on, technology remained fairly balanced, and casualties returned to a manageable level until spiking again in September 1918 following the German introduction of the BMW-powered Fokker D.VII.
The Royal Flying Corps did not operate exclusively on the Western Front, however. After some initial jurisdictional feuding with the RNAS, the RFC had assumed responsibility for the aerial home defense of Great Britain, thereafter regularly scrambling a hodgepodge of mostly second-line equipment in response to Zeppelin and Gotha attacks.
Outside of England and France, units also served in Egypt and Palestine, Mesopotamia, and Russia, providing support to British army operations in those theaters.
The Royal Naval Air Service mission was primarily, if not exclusively, the support of British maritime endeavors. This covered a wide range of activities, from antisubmarine patrols and general reconnaissance duties in connection with the fleet, to bombing missions against submarine pens and Zeppelin bases. To fulfill these missions, the RNAS developed a varied inventory that included floatplanes, flying boats, the first experimental torpedo-bombers, and lighter-than-air airships. Ships were also adapted to work with aircraft, leading to the balloon ship (which extended the effective range of vision of the group to which the balloon vessel was attached), the crane-equipped seaplane carrier, and, eventually, to the first flight-deck aircraft carriers.
In addition to new equipment, innovative techniques were also developed for work over the water, one of the most useful to the prosecution of the war being the so-called spider web. The spider web was an invisible grid over the English Channel and North Sea that provided an organized method for aircraft to use in searching for underwater mines and U-boats. Provision for aerial escort as part of the convoy scheme also contributed to the safety of Allied shipping as it crossed the Atlantic to and from North America.
As mentioned, the RNAS did not operate exclusively over the water. Throughout the war, naval units were deployed for land-based operations on the Western Front.And among the Allied forces, the RNAS could take credit for the first tentative attempts at strategic bombing. In the summer of 1916, the RNAS organized No. 3 Wing and equipped the unit with Sopwith 11/2 Strutters and Breguet bombers with the aim of attacking targets inside Germany. The group was stationed at Luxeuil, near Nancy, putting it within reach of manufacturing plants in the Saar River Valley. Bad weather – the perpetual enemy of aerial operations – kept No. 3 Wing grounded throughout much of its life, but its first – and most memorable – raid took place on 12 October 1916 when it attacked the Mauser Works at Oberndorf. The raid was a truly international operation involving not only the British naval unit but also French bombers and an escort of Nieuport fighters provided by the U.S. volunteers of the Lafayette Escadrille. By spring, however, the lackluster results achieved led to the breakup of the group and the reassignment of its crews to other units, many going to the navy's single-seat squadrons up near the channel coast. There, some pilots, such as Canadian ace Raymond Collishaw, would go on to great success flying the Sopwith Pup, Triplane, and later the immortal Camel, supplementing the RFC in support of army operations.
Relations between the two British aviation services were always somewhat tense, accusations of various intrigues going in both directions. The rivalry heightened to the point that a government committee merged the RFC and RNAS into the Royal Air Force on 1 April 1918.
Trenchard was ordered to run the Independent Force and General John Salmond became the RAF's first field commander. There is little evidence to indicate that a true merger of the two services really took place prior to the Armistice, however. There was a new 'RAF blue' uniform issued, but not many people are seen wearing it in wartime photos,most clinging not only to the old uniform but also to the practices and brief traditions of their earlier branch. Previously, naval squadrons were renumbered, each having '200' added to its original designation (e.g.,Naval Eight became No. 208 Squadron,RAF), and a few swaps of personnel were effected, probably the most notable being the transfer of RNAS ace Roderick Dallas to the command of No. 40 Squadron, an old RFC fighter unit. But these changes were largely cosmetic, and the real birth of the Royal Air Force is more likely found in the postwar struggles to remain funded and stay alive, all taking place under the stewardship of Trenchard. The fruits of his labor became apparent in 1940 when the RAF rose to the Nazi threat and achieved its finest hour during the Battle of Britain.