An American Atlas V rocket in the 501 configuration has successfully lifted off from Space Launch Complex 41 at Cape Canaveral carrying the US Air Force's X-37B spaceplane, a smaller version of the Space Shuttle. This will be the fourth mission of the X-37B which conducts top secret missions in orbit via payloads in it's payload bay. Liftoff occurred at 11:05 Local time, 15:05 UTC time on May 20th 2015.