There are certain laws of nature or physics that apply to any object that is lifted from the Earth and moved through the air. To analyze and predict airplane performance under various operating conditions, it is important that pilots gain as much knowledge as possible concerning the laws and principles that apply to flight. If, for example, the pilot allows the aeroplane to fly too fast, damage to the aeroplane’s structure might come about. If the pilot allows the aeroplane to fly too slow, the aeroplane can lose its lift and simply fall from the sky. It’s the pilot’s job to manage the aeroplane between these (and other) extremes. When approaching any extreme limits of the flight condition, the pilot must have a good understanding of what’s about to happen.

This section examines the fundamental physical laws governing the forces acting on an aircraft in flight, and what effect these natural laws and forces have on the performance characteristics of aircraft. To control an aircraft, be it an airplane, helicopter, glider, or balloon, the pilot must understand the principles involved and learn to use or counteract these natural forces.