Final answer:
The first extensive use of aircraft in warfare was during World War I, marking the beginning of significant aerial combat and the use of technology that transformed modern warfare.
Step-by-step explanation:
The first extensive use of aircraft occurred during World War I. During this conflict, both sides utilized aircraft for various purposes, including reconnaissance, strafing trenches with machine guns, and dropping bombs. Pioneers like the Wright Brothers, who developed the first controlled, powered, and sustained heavier-than-air human flight in 1903, set the stage for these advancements. As the war raged on, pilots began engaging each other in the air, leading to the phenomenon of "dogfights" and the emergence of celebrated fighter aces. This marked the beginning of significant aerial combat history, with military technology transforming warfare.