Stratolaunch’s Roc carrier plane flies above California’s Mojave Desert. (Stratolaunch via Twitter) Stratolaunch, the aerospace company founded by the late Seattle billionaire Paul Allen, put the world’s biggest airplane through its second flight test today, two years after the first flight. Today’s takeoff from California’s Mojave Air and Space Port at 7:28 a.m. PT marked the first time the plane, nicknamed Roc after the giant bird of Arabian and Persian mythology, got off the ground since Stratolaunch’s acquisition by Cerberus Capital Management in October 2019. Roc rose as high as 14,000 feet and traveled at a top speed of 199 mph during a flight that lasted three hours and 14 minutes — which is close to an hour longer than the first flight on April 13, 2019. During that earlier flight, the airplane reached a maximum speed of 189 mph and maximum altitude of 17,000 feet.