Parabolic flight is like being on a roller coaster. Airplanes fly up very quickly and then drop down quickly. When the plane is flying up, it feels like going down a hill on a roller coaster. When the plane is dropping down, it feels like going up a hill on a roller coaster. Special types of airplanes are used to do this and they can fly up and down many times in a row, creating a roller coaster ride in the air! Scientists use these planes to help do experiments, like finding out what it would be like to be in a zero-gravity environment.