Wake turbulence

Wake turbulence is like a swirling or whirling of air that is left behind an aircraft when it takes off or lands. It's kind of like leaving a trail of bubbles behind you in the water. The air swirls around and can bother other airplanes that are flying nearby. So pilots and air traffic controllers have to be very careful to make sure other planes don't fly too close behind the one that created the wake turbulence.