You may be asking, "How does Circular Motion relate to the Air Force?"
Remember how we talked about a violently turning fighter in the introduction to this lesson? Imagine a fighter pilot suddenly realizing that he has been targeted by a deadly heat-seeking missile. His only hope is to outmaneuver the missile. He quickly rolls into a steep left bank and pulls hard on the stick, causing the missile to overshoot and explode out of range.
Circular motion was at work here. As the pilot rolled and pulled on the stick, he caused the jet to turn to the left, forcing its formerly straight path to curve. This curved path had a radius, and the jet had some definite airspeed. Knowing these two parameters, we can easily figure out how many Gs the pilot felt from the radial acceleration formula.