If you were a private pilot you could not fly a Boeing 747. Not only don't you have an ATP (airline transport pilot) certificate, but you don't have training on flying larger and more complex aircraft. The same goes for sport pilots: Sport pilots can fly only sport aircraft that fit the definition of light-sport. Fortunately, the rules for new light-sport aircraft are as dramatically reworked as the sport-pilot certification rules. It's as though the FAA threw out many of their preconceived ideas about how complex a plane needs to be and started over with simpler rules. The result is lower-cost flying!