Mystery Shuttle Lands After Two-Year Flight

The X-37B Orbital Test Vehicle is pictured in this US Air Force handout

The US military's top-secret version of the space shuttle has completed a nearly two-year-long classified mission.The space plane, known as the X-37B, landed at Vandenberg Air Force Base on the Southern California coast on Friday after circling the Earth for 674 days.What the shuttle was doing during thattime remains a mystery.


The Air Force says the space planes, also known as Orbital Test Vehicles,"perform risk reduction, experimentation and concept-of-operations development for reusable space vehicle technologies".An Alliance Atlas 5 rocket carrying the X-37B lifts off in December 2012Others, including the Secure World Foundation, a nonprofit group that promotes the peaceful exploration of space, speculate that the secrecy is almost certainly tied to the presence ofnational intelligence-related hardware being tested or evaluated.Costs associated with the programme are also classified.Upon landing of the latest mission, the Air Force simply said the aircraft had been conducting "on-orbit experiments".It was the second flight for this X-37B. The same plane circled the planet for more than seven months in 2010. A second X-37B spacecraft blasted off inMarch 2011 and spent more than a year in orbit.At 29ft (8 metres) long, the Boeing-built planes are about one-quarter the size of NASA's old space shuttles.They are equipped with solar panels that unfurl to charge its batteries once in orbit.The Air Force said it plans to launch the fourth X-37B mission from Cape Canaveral, Florida, next year.By posting a comment you are agreeing to abide by ourTerms & Conditions. See ourHouse Rules and FAQs.0 commentsSign in723 people listeningThe US military's top-secret version of the space shuttle has completed a nearly two-year-long classified mission.The space plane, known as the X-37B, landed at Vandenberg Air Force Base on the Southern California coast on Friday after circling the Earth for 674 days.What the shuttle was doing during thattime remains a mystery.The Air Force says the space planes, also known as Orbital Test Vehicles,"perform risk reduction, experimentation and concept-of-operations development for reusable space vehicle technologies".An Alliance Atlas 5 rocket carrying the X-37B lifts off in December 2012Others, including the Secure World Foundation, a nonprofit group that promotes the peaceful exploration of space, speculate that the secrecy is almost certainly tied to the presence ofnational intelligence-related hardware being tested or evaluated.Costs associated with the programme are also classified.Upon landing of the latest mission, the Air Force simply said the aircraft had been conducting "on-orbit experiments".It was the second flight for this X-37B. The same plane circled the planet for more than seven months in 2010. A second X-37B spacecraft blasted off inMarch 2011 and spent more than a year in orbit.At 29ft (8 metres) long, the Boeing-built planes are about one-quarter the size of NASA's old space shuttles.They are equipped with solar panels that unfurl to charge its batteries once in orbit.The Air Force said it plans to launch the fourth X-37B mission from Cape Canaveral, Florida, next year.