Scaled Composites has confirmed that its Stratolaunch Carrier Aircraft, the world’s biggest plane, will begin testing next year. The concept of the plane is a product of combined innovation from Microsoft co-founder Paul Allen and Burt Rutan, founder of Scaled Composites. The plane is currently under construction at Mojave Air and Spaceport in California, and will eventually have a wingspan of 385 feet.

Initially, the system was intended to just deliver satellites weighing up to about 13,500lbs (6,124 kg) into orbits between 112 miles and 1,243 miles above Earth. However, instead of just satellites, the Stratolaunch airplane could launch a Dream Chaser spaceship carrying a satellite. The Stratolauncher will climb to 30,000 feet and launch a rocket at high altitude, avoiding the huge fuel costs of launching from Earth. The Dream Chaser will then go into orbit and deliver a satellite. The idea is for the Stratolaunch Carrier is to act as a giant air pad in the sky, allowing payloads to reach space faster and at a lower cost than existing technologies.

“It could provide a highly responsive capability with the potential to reach a variety of LEO [low Earth orbit] destinations and return astronauts or payloads to a U.S. runway within 24 hours,” said Chuck Beames, president of Allen’s Vulcan Aerospace. “Stratolaunch’s ability to launch from variable locations will enable satellites and humans to be efficiently inserted into their most optimal orbit at a time of the customer’s choosing.”

The first launch of the space launch vehicle is likely to take place in 2018. There are currently several launch sites under consideration, including ones at the Kennedy Space Center, Wallops Island and Vandenberg AFB. Scaled Composites president Kevin Mickey says the company has so far built “roughly 200,000lbs of composite structure” for the vehicle so far. It will be powered by six 747-class engines during its first flight in 2016 and will weigh 1.2 million pounds.