A giant aircraft capable of launching satellite-laden rockets into space has been unveiled at a hangar in the Mojave desert in California.
Stratolaunch, said to be the largest airliner ever built, weighs 500,000lbs (226,796kg) and has a wingspan measuring 385ft (117 metres) - the world's biggest.
In a blog post, Stratolaunch Systems Corporation chief executive Jean Floyd said: "This marks a historic step in our work to achieve Paul G Allen's vision of normalising access to low Earth orbit.
"This is a first-of-its-kind aircraft, so we're going to be diligent throughout testing."
The aircraft will begin testing its fuel systems and engines on the ground at its air and space port in the California desert in the next few weeks.
Support structures were recently removed from the plane, allowing it to rest on its 28 wheels for the first time.
He added the project would lead to a greater flexibility than ground-based rocket launches and offer better cost effectiveness for cargo and human missions to space.