The world's largest airplane - a Stratolaunch behemoth with two fuselages and six Boeing 747 engines - has made its first test flight in California.
The mega jet carried out its maiden voyage over the Mojave desert on Saturday.
It is designed to carry into space, and drop, a rocket that would in turn ignite to deploy satellites.
It is supposed to provide a more flexible way to deploy satellites than vertical takeoff rockets because this way all you need is a long runway for takeoff.
It was built by an engineering company called Scaled Composites. The aircraft is so big its wing span is longer than a football field, or about 1.5 times that of an Airbus A380.
Specifically, the wing span is 117 meters; that
of an Airbus A380 is just under 80. The plane flew Saturday for about two and a half hours, Stratolaunch said. Until now, it had just carried out tests on the ground.
It hit a top speed of 304 kilometers per hour (189 mph) and reached an altitude of 17,000 feet, or 5,182 meters.
"What a fantastic first flight," said Jean Floyd, CEO of Stratolaunch.
"Today's flight furthers our mission to provide a flexible alternative to ground launched systems," he added.
Stratolaunch was financed by Paul Allen, a co-founder of Microsoft as a way to get into the market for launching small satellites.
But Allen died in October of last year so the future of the company is uncertain.