Stratolaunch's supersized aircraft could someday launch a space plane to orbit
Microsoft co-founder Paul Allen has a vision for making trips to space more like air travel. Well, kinda.

The full lineup of planned Stratolaunch craft.
What do you do with the world's largest plane? If you're billionaire Paul Allen, you attach another plane to its belly that can then be launched into space.
That's the latest vision for the Microsoft co-founder's Stratolaunch, a kind of Spruce Goose for the 21st century.
Of course Allen and Stratolaunch, the startup that shares a name with its largest craft, hope their massive plane will see much more duty than Howard Hughes' one-flight wonder. On Monday, the company unveiled a new lineup of launch vehicles that would be carried aloft by the Stratolaunch and then blast off for orbit.
Stratolaunch was built to launch a Pegasus XL rocket from the air, but three other compatible launch vehicles are under development, including a three-core rocket that could carry 15 times Pegasus' payload and a space plane that could eventually carry humans to orbit.
"We are excited to share for the first time some details about the development of our own, proprietary Stratolaunch launch vehicles," said Stratolaunch CEO Jean Floyd in a release. "Whatever the payload, whatever the orbit, getting your satellite into space will soon be as easy as booking an airline flight."
In addition to the Pegasus, which can carry 370 kilograms (816 pounds) to orbit and is set to launch from a Stratolaunch for the first time in 2020, the company is building its own Medium Launch Vehicle (MLV), with nearly 10 times the payload capability, and the aforementioned three-core MLV-Heavy.
The fully reusable space plane, meanwhile, is in the midst of a design study with no date currently set for when it might make its maiden flight.
All planned Stratolaunch vehicles are significantly smaller than the big rockets from the likes of SpaceX, which isn't really a direct competitor. Rather than launching big satellites or aiming for the moon and beyond, the company hopes to enable "convenient, affordable, routine, airline-style access to space that empowers the world's problem solvers, so that they can collect rich and actionable data and drive advancements in science, research, and technology from space."
This likely means working primarily in low-earth orbits and with smaller satellites or orbiting space stations. Startups like Virgin Orbit and Rocket Lab hope to offer similar services with payload capabilities near the range of the Stratolaunch/Pegasus combination. The new launch vehicle offerings from Stratolaunch would enable the company to carry a much wider (and heavier) variety of payloads to orbit.
As such, the company could occupy an interesting middle ground, along with the financially troubled FireFly Aerospace, between the smallsat-launching startups and big rocket companies like SpaceX, United Launch Alliance and Jeff Bezos' Blue Origin.
We'll have to wait a while to see if Stratolaunch's big vision gets off the ground. The first flight of its proprietary MLV isn't planned until 2022.
Look, up in the sky: NASA orders a supersonic X-Plane, easy on the boom
Crowd Control: A crowdsourced science fiction novel written by CNET readers.