Fighter aviation

Early in the war aircraft were used for reconnaissance and artillery spotting, and airmen shot at each other with pistols and rifles. The breakthrough was a gun firing forward, along the line of flight. In spring 1915 the Frenchman Roland Garros fitted steel wedges to his propeller, and that summer the Germans introduced the Fokker monoplane with a synchroniser. This gave them the upper hand, known as the Fokker Scourge, which lasted until spring 1916.

From 1916 fighters were grouped into specialised squadrons, in Germany the Jagdstaffeln, formed with Oswald Boelcke's help. They fought for command of the air, escorted reconnaissance aircraft and bombers, attacked observation balloons and, late in the war, troops on the ground. By 1917 whole formations of dozens of machines fought over the front. The war's most successful ace was Manfred von Richthofen, credited with 80 victories.