Top-secret unmanned X-37B space plane lands after yearlong mission

The X-37B space plane, an unmanned US Air Force test vehicle, returned to Earth on Saturday after a 469-day classified mission.

The unmanned X-37B, also known as Orbital Test Vehicle-2 (OTV-2), glided back to Earth on autopilot, touching down at California's Vandenberg Air Force Base at 5:48 a.m. PDT (8:48 a.m. EDT, 1248 GMT), Space.com reported.

The reusable Boeing-built plane is the nation's "newest and most advanced re-entry spacecraft" was executed "safely and successfully," the Air Force said in a statement cited by CNet News. 

The spacecraft, 29 feet long and with a 15-foot wingspan, looks like a miniature version of the now-retired NASA space shuttles, according to ABC News.

"With the retirement of the space shuttle fleet, the X-37B OTV program brings a singular capability to space technology development," Air Force Lt. Col. Tom McIntyre, X-37B program manager, said in the statement. 

"The return capability allows the Air Force to test new technologies without the same risk commitment faced by other programs.

"We're proud of the entire team's successful efforts to bring this mission to an outstanding conclusion."

It was the X-37B program's second-ever spaceflight. The X-37B, designed to stay in extended Earth orbits, remained in space for 225 days during its maiden mission in 2010.

The Huffington Post quoted Col. Nina Armagno, 30th Space Wing commander at Vandenberg as saying: "Team Vandenberg has put in over a year’s worth of hard work in preparation for this landing and today we were able to see the fruits of our labor. I am so proud of our team for coming together to execute this landing operation safely and successfully."

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