It was when machine guns came into use in the latter part of 1914 that aerial combat really began. Some larger aircraft did carry dedicated gunners, such as the German AEG G.IV bomber pictured ...

50 Caliber Machine Gun, Heavy barrel is an automatic ... mounts and most vehicles as an anti-personnel and anti-aircraft weapon. The gun is equipped with leaf-type rear sight, flash suppressor ...

The MK19 Grenade Machine Gun can defend against hovering rotary-wing aircraft, destroy lightly armored vehicles, fire on suspected enemy positions, and provide high-volume fire into an engagement ...