The very first tactical approach of planes was only related to their combined use with artillery. However as the war progressed, they were soon pushed into new roles, which created branches -and tactics- of their own. The Fighters are a good example of this. They emerged of necessity, when aviation met intelligence gathering in an industrial scale. On the ground, spies were shot, but the first aviators, even from opposite sides, gently waved their hands in salute when meeting in the air. Of course this "chivalry" image persisted in culture, but the grim reality soon take over when when a pilot first shot another with a pistol. They were attempts, with grenades, lead balls, hooks, cavalry rifles, until the most deadly weapon of the war made its way in turn, amidst the canvas and ropes of the first improvized fighters. The first MG-armed serie fighters were the Fokker Eindecker E-I which advantageously replaced the prolific bird-like Erich Taube, way too frail for a machine-gun. From then on, the plane itself, thanks to the interrupter gear, could be aimed by the pilot on its target. And the first fighter tactics were born.
Max Immelman (which gave its name to a distinctive loop) was among the first to devise air-to-air combat tactics. The Germans pilots of the Luftstreitkrafte in general were the first to codify these tactics, especially Oswald Boelcke, his own great rival. The latter indeed would be considered as the Father of Air Fighting Tactic, and wrote the famous "Boelcke's Dicta", still bedside book for pilots at the eve of the Spanish Civil War (More on this below, see "aces"). With his Jasta 2 in 1916, Boelke had his men practising strict formations, repeating tactical drills. One of his most avid students were Manfred von Richthofen and Erwin Böhme. At the time of the second "Fokker scourge" in April 1917, German pilots were the best in the world, making for inferior numbers.
Classed in victory numbers, these are the Aces of ww1. Some raised to national superstar, almost demigod status, like Manfred Von Richtofen, the "Red Baron" after his brightly colored Dr.I. The very first (for which Newspapers coined the famous "ace") was Adolphe Pégoud after he downed seven German aircraft. The "victory" standards varied between different air services and countries, and verifications on the ground were often problematic as one might expected. However it was generally accepted that a pilot became an "ace" after five victories. It could seems low, as in an average dogfight a skilled pilot could down several planes at once, on the same day (two-three sorties), but bear in mind life expectancy of a pilot was then short, at least on the Western front. There were also many cases of unconfirmed victories. Sources get confused despite production numbers compared to scores of squadrons or jasta. But they are in fact not that helpful and modern Historians still have these counts evolving. These figures below are those generally accepted today.
The "case of aces" shot down, despite his young age, no less than 80 aircrafst. He was long to became an ace, arriving in march 1916 to only be considered one in October, but until April 1918 he would be raised at a National level of fame unmatched at the time. He was noted as a fine tactician and marksman, not as dashing as his brother Lothar (40 Victories) or Werner Voss. He was given his own Jasta 11 in January 1917, soon known as the "flying circus". Although disciplined in tactics, these pilots had their brightly colored planes used as a psychological terror advertisement. This coincided with the adoption of the Fokker D.VII (developed with Richtofen), soon one of the best -if not the best- fighter of WW1, to create an allied eclipse in the air ("Bloody April") which will last until May and the arrival in numbers of the new allied SE.5, Sopwith Camel, and SPAD S.XIII. Richtofen was ultimately killed in action by an unknown pilot (controversy still rages on) one year after, on 21 April 1918. Although his score is largely beaten by WW2 aces like Erich Hartmann and his 352 victories, he is best remembered and was depicted in many movies and fictions, perhaps because of the Nazi shadow lurking above Hartmann and most German ww2 pilots.