The first airplane flight was on Dec. 17, 1903, in North Carolina. By the middle of 1914, pilots on opposing sides of World War I were throwing bricks and shooting pistols at each other, and soon enough machine guns were mounted on planes and pilots began keeping score.
The dogfights of World War I were more about entertainment and sparking morale (on the front and at home) than military strategy (air forces did not become essential to militaries until World War II), but dogfights were still an important aspect of the militaries involved in WWI.