Nearly a year after it first emerged, the Stratolaunch, the largest plane ever built, is getting ready for its first flight later this year.

The aircraft, which weighs approximately 500,000 pounds, can carry payloads up to 550,000 pounds and has a wingspan longer than a football field (385 feet), is so big that it needs two cockpits. It's powered by six Boeing 747 engines Stratolaunch Systems CEO, Jean Floyd said last year.

Microsoft co-founder Paul Allen, who is backing the project, said that when the plane takes flight, it will be an incredible experience. "When you see that giant plane, it's a little nutty," Allen said in an interview with Wired.

STRATOLAUNCH: WORLD'S LARGEST PLANE FINALLY EMERGES

In the interview, Allen added that the Stratolaunch has one purpose: "getting vehicles in orbit."

The plane, which has 28 wheels, was built in the Mojave desert inside a custom-built hangar.

According to The Sun, the Stratolaunch has gone through two taxi tests in the past few months, reaching speeds of 28 mph and 46 mph, respectively. There are three additional tests needed to see if it can reach 138 mph, required for the plane to take off.

On Monday, the company announced that its family of launch vehicles will enter regular service in 2020, using the giant plane as a launch pad, capable of sending out launch vehicles stocked with satellites in an effort to "make access to space convenient, affordable, and routine."

“We are excited to share for the first time some details about the development of our own, proprietary Stratolaunch launch vehicles, with which we will offer a flexible launch capability unlike any other,” said Floyd in a statement. “Whatever the payload, whatever the orbit, getting your satellite into space will soon be as easy as booking an airline flight.”

The new launch vehicles include:

- the Pegasus, which can carry payloads up to 370 kilograms, schedule to have its first flight in 2020;

- a Medium Launch Vehicle, capable of carrying 3,400 kilograms (first flight in 2022);

- Medium Launch Vehicle – Heavy, with a 6,000 kilogram payload capability;

- and a Space Plane, described as "a fully reusable space plane that enables advanced in-orbit capabilities and cargo return."

The company, founded in 2011, said it will have more to add about the launch vehicles before the end of the year.

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