Secretive Air Force X-37B mini-shuttle breaks orbital record

The Air Force’s secretive X-37B mini-shuttle on Saturday broke its own record of time spent in orbit.

The experimental space plane spent its 675th day in space on a mission known as Orbital Test Vehicle-4, or OT-4. It previously spent 674 days in orbit before landing at Vandenberg Air Force Base in California in October 2014.

"The X-37B remains on orbit," said Capt. Annmarie Annicelli, an Air Force spokeswoman at the Pentagon. "We are extremely proud of its performance and its contributions to advancing space technologies."

The 11,000-pound spacecraft with a 15-foot wingspan launched from Cape Canaveral Air Force Station in May 2015 atop a United Launch Alliance Atlas V rocket. At the time, the Air Force said the X-37B allows reusable spacecraft technologies to be tested in space, returned to Earth and possibly reflown before full deployment.

The Boeing-built X-37B is designed to stay in orbit for 270 days, but the missions began outpacing that number when the second mission hit the 469-day mark.

Officials have not said when the mini-shuttle will land, but it’s expected to touch down on Kennedy Space Center’s three-mile runway much like the space shuttle did for the last time nearly six years ago.

Contact Kelly at aekelly@floridatoday.com or 321-242-3715. Follow him on Twitter and Facebook at @EmreKelly.

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