The monstrous 100-ton Stratolaunch airplane rolled out of its hangar in the Mojave Desert Wednesday.
It's the first time Eyewitness News has seen the twin-hulled design, which features a 385-foot wingspan, making it the world's widest airplane.
It will now undergo ground tests. Its first flight could take place as early as 2019.
Stratolaunch is intended to carry a rocket slung beneath the wing and release it at 35,000 feet. The concept is that the rocket will then launch into space and deliver satellites into orbit.
Microsoft co-founder Paul Allen owns the company building the plane.