Eddie Rickenbacker and Dick Bong: The Lives of America's Top Fighter Aces during the World Wars

At first, airplane improvements occurred in an ad hoc, almost accidental manner during World War I. However, when pilots’ mounting of armaments on airplanes proved a successful means of defeating other aircraft and even attacking men on the ground, a much more active and systematic development of warplanes began across the continent. Each advance prompted a countermeasure, as the two sides strove for primacy in a deadly, unforgiving environment which rewarded real advances in equipment and tactics with survival and punished poor ideas with death. Before long, relatively powerful, heavily armed aircraft buzzed through the skies over battle-stained Europe, tearing each other apart with furious gusts of machine gun fire and sending many of the vaunted dirigibles plunging, burning, to the ground. The new era of fighting aircraft arrived in dramatic fashion, raising successful pilots to celebrity or heroic status, and laying the groundwork for the tremendous potential of airpower to achieve its next logical expansion in World War II and beyond.
Rickenbacker's World War I service won him the Medal of Honor, along with more awards for valor than any other person fighting in World War I. But participating in the wars was not nearly enough time in the air for the ambitious Rickenbacker. When he was not setting new records in the air, he was setting new speed records on the ground, most notably as a first-generation race car driver who not only drove cars but designed them.
By the time World War II arrived, the fighter airplane was a much different beast than the purpose-built aircraft-hunting machines of 1917 and 1918. Though propellers still provided motive force, greatly increased engine power allowed these aircraft to slice through the sky at speeds of 200 miles per hour (mph), 300 mph, or even in excess of 400 mph when flying flat-out. Service ceilings jumped to 25,000 feet, 30,000 feet, or higher.