When Archduke Ferdinand was assassinated on the 28th of June 1914, it was just over a decade since the Wright brothers’ first twelve second flight at Kitty Hawk.
In the intervening years advances in range and reliability proved that the airplane was a viable, if still somewhat exotic, means of transport. In 1909 Bleriot made the first flight across the English Channel. In 1913 Roland Garros made the first cross Mediterranean flight, from the south of France to Tunisia.
There was also, in this period, some initial understanding of the military implications of the airplane. After Bleriot's flight H. G. Wells was to write, prophetically, that "…this is no longer, from a military point of view, an inaccessible island." In 1911 the Italians, at war with Turkey in Libya, became the first to make military use of the airplane, dropping grenades from a German-built monoplane. In 1912 they also dropped bombs from an airship.
When war broke out the number of aircraft on all sides and all fronts was very small. France, for example, had less than 140 aircraft at the start of the war. By the end of the war she fielded 4,500 aircraft, more than any other protagonist. While this may seem an impressive increase, it does not give a true indication of the amount of aircraft involved. During the war France produced no less than 68,000 aircraft. 52,000 of them were lost in battle, a horrendous loss rate of 77%. The period between 1914 and 1918 saw not only tremendous production, but also tremendous development in aircraft technology.
A typical British aircraft at the outbreak of the war was the general purpose BE2c, with a top speed of 116 km/h (72 mph). Powered by a 90 hp engine, it could remain aloft for over three hours. By the end of the war aircraft were designed for specific tasks. Built for speed and maneuverability, the SE5a fighter of 1917 was powered by a 200 hp engine and had a top speed of 222 km/h (138 mph).
Britain 's most famous bomber, the Handley-Page O/400, could carry a bomb load of 900kg (2000 lb) at a top speed of 156 km/h (97mph) for flights lasting eight hours. It was powered by two 360 hp engines.
In 1914 it was important that aircraft be easy to fly, as the amount of training that pilots received was minimal, to say the least. Louis Strange, an innovative pilot from the opening stages of the war, was an early graduate of the RFC (Royal Flying Corps) flight school. He began flying combat missions having completed only three and a half hours of actual flying time. For this reason aircraft were designed for stability. By the end of the war stability had given way to manoeuvrability. The famous Sopwith Camel was a difficult aircraft to fly, but supremely agile. Not only did aircraft become faster, more maneuverable and more powerful, but a number of technologies that were common at the start of the war had almost disappeared by the end of it. Many of the aircraft in 1914 were of "pusher" layout. This is the same configuration that the Wright brothers used, where the propeller faced backwards and pushed the aircraft forward.
The alternative layout where the propeller faces forwards and pulls the aircraft, was called a "tractor" design. It provided better performance, but in 1914 visibility was deemed more important than speed. World War One marked the end of pusher aircraft.
Another technology that scarcely survived the war was the rotary engine. In this type of engine the pistons were arranged in a circle around the crankshaft. When the engine ran, the crankshaft itself remained stationary while the pistons rotated around it. The propeller was fixed to the pistons and so rotated with them. Rotary engines were air cooled, and thus very light. They provided an excellent power-to-weight ratio, but they could not provide the same power that the heavier in-line water cooled engines could. Although they remained in use throughout the war, by 1918 Sopwith remained the last major manufacturer still using them.
The rapid pace of technological innovation was matched by a rapid change in the uses to which aircraft were put. If in 1914 there were few generals who viewed aircraft as anything more than a tool for observation and reconnaissance (and many of them had great reservation even to that use) by the end of the war both sides were integrating aircraft as a key part of their planned strategies. While the plane did not play the decisive roll that it was to play in later conflicts, the First World War proved their capabilities. It was during this period that the key tasks that aircraft could perform were discovered, experimented with, and refined: observation and reconnaissance, tactical and strategic bombing, ground attack, and naval warfare. With the growing importance and influence of aircraft came the need to control the air, and thus the fighter was born.
One of the many innovations of World War I, aircraft were first used for reconnaissancepurposes and later as fighters and even bombers. Consequently, this was the first war which involved a struggle for control of the air, which turned it into another battlefield, alongside the battlefields of the land and the sea. Yet given the early state of development of aircraft at the time, aerial combat missions played a relatively small part in determining the outcome of the war. It would take another world war before military aircraft would be used to their full potential.
The dawn of air combat
Aircraft were initially used as mobile observation vehicles with the responsibility of mapping enemy positions below. This was an improvement over previous observation vehicles such as the Zeppelin, which was too large and slow moving (and therefore an easy target) and the observation balloon, which had to be tethered to the ground and wasn't very mobile.
As Dickson predicted, both the Entente and Central powers first used aircraft only for observation purposes. When rival observation planes crossed paths, the aviators at first exchanged smiles and waves. This soon progressed to throwing bricks, grenades, and other objects, even rope, which they hoped would tangle the enemy plane's propeller. Eventually pilots began firing handheld firearms at enemy planes. Once the guns were mounted to the aircraft, the era of air combat began.
Problems mounting machine guns
Another major limitation was the early mounting of machine guns, which was awkward due to the position of the propeller. It would seem most natural to place the gun between the pilot and the propeller, so they would be able to aim down its sight as well as service it during a gun jam. However, this gun position presents an obvious problem - the bullets would fly directly into the propeller.
Frenchman Roland Garros attempted to solve this problem by attaching metal deflector wedges to the blades of his propeller, which he hoped would guide bullets away. Garros managed to score several kills with his deflector modification, yet it was still an inadequate and dangerous solution, as when Germany tried this, their steel-jacketed bullets shattered the wedges. The French Hotchkiss machine gun (as well as the Lewis gun) used by the Allies used more conventional copper- and brass-jacketed ammunition.
1915: The Fokker Scourge
In 1915, Anthony Fokker designed the synchronizer gear, which turned the tide of war in Germany's favor. This ingenious device mechanically linked the gun to the propeller, allowing it to fire between blades. This was first fitted in the spring of 1915 to the production prototypes of the Fokker Eindekker, known as the Fokker M.5K/MG, making it top-of-the-line in design, maneuverability (although the Eindekker used wing warping for roll control), and most importantly, gun placement. Leutnant Kurt Wintgens, on July 1, 1915, scored the earliest known victory for a synchronized gun-equipped fighter with his M.5K/MG over a two-seat Morane Saulnier Parasol near Luneville, France. The result was devastating for the Allied powers, and gave the Germans almost total control of the air. Soon Allied planes were forced to flee for home at the mere sight of German monoplanes. A solution was needed, and quickly.
April 1917: Bloody April
In April the Allies launched a joint offensive with the British attacking near Arras in Artois, northern France, while the French Nivelle Offensive was launched on the Aisne and the air forces were called on to provide support, predominantly in reconnaissance and artillery spotting.
However, the Germans were prepared for the offensive, and were equipped with the new Albatros D-III, "the best fighting scout on the Western Front” at the time.
The month became known as Bloody April by the Allied air forces. The Royal Flying Corps suffered losses so severe it came close to being annihilated. However, they managed to keep the German Air Force on the defensive, largely preventing them from from using their planes on bombing or reconnaissance missions to assist their troops on the ground.
Shortly after "Bloody April", the Allies re-equipped their squadrons with new planes such as the Sopwith Pup, and SE5a which helped tip the balance back in their favor. The Germans responded with new fighters as well, such the Fokker Dr.I but these were countered by the British Sopwith Camel and French SPAD S.XIII. As a result, neither side managed to take a clear technological advantage for the remainder of the war, but eventually the Allies would gain the advantage in numbers and material toward the end of the year.
Up to 1918: the final years of war
The final year of the war (1918) saw increasing shortages of supplies on the side of the Central Powers. Captured Allied planes were scrounged for every available material, even to the point of draining the lubricants from damaged engines just to keep one more German plane flyable. Manfred von Richthofen, the famed Red Baron credited with around 80 victories, was killed in April, possibly by an Australian anti-aircraft machinegunner (although Royal Air Force pilot Captain Arthur Roy Brown was officially credited), and the leadership of Jagdgeschwader 1 eventually passed to Hermann Göring, future head of Nazi Germany's Luftwaffe. Germany introduced the Fokker D.VII, both loved and loathed to the point that surrender of all surviving examples was specifically ordered by the victorious allies.
This year also saw the United States increasingly involved. While American volunteers had been flying in Allied squadrons since the early years of the war, it wasn't until 1918 when all-American squadrons begin patrolling the skies above the trenches. At first, the Americans were largely supplied with second-rate weapons and obsolete planes, such as the Nieuport 28. As American numbers grew, equipment improved, including the SPAD S.XIII, one of the best French planes in the war. By the end of World War I, four American aviators were awarded the Medal of Honor: Fighter pilots Eddie Rickenbacker and Frank Luke, along with recon pilot Harold Goettler and his observer, Erwin Beckley, a member of the Kansas Army National Guard who had volunteered for aviation duty. Beckley was the first of only three National Guard aviators to be awarded the Medal of Honor during the 20th century.
Impact
By the war's end, the impact of air missions compared to the ground war was relatively small. This was partly due to its restricted funding and use, as it was, after all, a new technology. Some, such as General William Mitchell, claimed that "the only damage that has come to [Germany] has been through the air”.
It took World War II for the rest of the world to be convinced of this. Finally, in 1946, Mitchell was posthumously awarded the Congressional Gold Medal of Honor, "in recognition of his outstanding pioneer service and foresight in the field of American military aviation".