A company owned by Microsoft's co-founder just unveiled the biggest plane in the world

For decades, Ukraine's Antonov AN-225 has reigned supreme as the largest plane in the world.

That is, until now.

On Thursday, Stratolaunch rolled its low orbit launch aircraft out of the company's hangar in the California desert for the first time.

With wings spanning 385 ft, it is the world's largest airplane by wingspan - besting the AN-225's 290 ft. wingspan.

The aircraft is also 238 ft. long and 50 ft. tall.

Like the AN-225, the Statolaunch plane is also powered by six high-bypass ratio turbofan engines.

Stratolaunch - owned by Microsoft co-founder Paul Allen - intends to use the aircraft to move forward with its vision to "provide convenient, reliable, and routine access to low Earth orbit."

"This marks a historic step in our work to achieve Paul G. Allen's vision of normalizing access to low Earth orbit," Stratolaunch Systems Corporation CEO Jean Floyd said in a statement. "We have a lot of exciting activity ahead as we enter the testing process, and we look forward to sharing our progress during the coming months."

Ahead of the roll out, Stratolaunch removed the three-story high scaffolding around the plane and lowered the 500,000 lbs. craft onto its 28 wheels for the first time. The Stratolaunch plane is expected to undergo ground tests, engine runs, and taxi tests before ultimately making its first flight.

The company plans to use the aircraft as a platform to launch rockets into orbit. Which is why it has a designed maximum takeoff weight of 1.3 million pounds. In fact, Stratolaunch believes the aircraft will be one day be able to deliver as many as three rockets into orbit on a single mission.

According to Stratolaunch, the aircraft is on track to perform its first launch demonstration in 2019.