The world's largest airplane – a Stratolaunch behemoth with two fuselages and six Boeing 747 engines – made its first test flight on Saturday in California.
The mega jet carried out its maiden voyage over the Mojave desert.
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 wingspan is longer than a football field, or about 1.5 times that of an Airbus A380. Specifically, the wingspan is 117 meters; that of an Airbus A380 is just under 80.
The jet lifted off from Mojave Air and Space Port shortly before 7 a.m. local time Saturday and climbed into the desert sky 70 miles (112 kilometers) north of Los Angeles. The jet flew 2.5 hours, achieving a maximum speed of 189 mph (304 kph) and altitudes up to 17,000 feet (5,181 meters), the company said.
"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.
The previous wingspan leader was Howard Hughes' World War II-era eight-engine H-4 Hercules flying boat – nicknamed the Spruce Goose. Surviving in an aviation museum, it has an approximately 320-foot (97.5-meter) wingspan but is just under 219 feet (67 meters) long.
While Stratolaunch calls its aircraft the world's largest, other airplanes exceed it in length from nose to tail. They include the six-engine Antonov AN 225 cargo plane, which is 275.5 feet (84 meters) long, and the Boeing 747-8, which is just over 250 feet (76.3 meters) long.