The world's largest airplane was rolled out for the first time Wednesday. Stratolaunch , which is designed to release rockets that will carry satellites into space has a 385-foot wingspan, features six engines used by the Boeing 747, stands 50 feet tall and can carry more than 500,000 pounds of payload. And it has those 28 wheels. The twin-fuselage aircraft, was pulled out of its Mojave Air and Space Port hangar in California to begin fueling tests the first of many ground tests. Continue to see more photos...