A mysterious unmanned space plane belonging to the US Air Force made landing at NASA’s Kennedy Space Center in Florida after completing a secret two-year mission. The experimental space plane named X-37B completed a classified mission of two years, the US Air Force said.
The X-37B unmanned plane looks like a miniature space shuttle. It landed at 7:47 am EDT (1147 GMT) on Sunday. The Boeing-built space plane touched down on a runway which was previously used for landings of the now-mothballed space shuttles, the Air Force said.
The unmanned X-37B was launched in May 2015 from Cape Canaveral Air Force Station. An Atlas 5 rocket built by United Launch Alliance, a partnership between Lockheed Martin Corp and Boeing Co, carried the plane.
There are two X-37B planes in the fleet of US Air Force. One of these carried out unspecified experiments for over 700 days while in orbit.
It was US Air Force Rapid Capabilities Office’s fourth and the lengthiest mission so far for the secretive program.
The orbiters “perform risk reduction, experimentation and concept-of-operations development for reusable space vehicle technologies,” the Air Force said. The cost of the program is also classified.
According to the Secure World Foundation, a nonprofit group which promotes the peaceful exploration of space, the secrecy of the mission suggests that the intelligence-related hardware is being tested or evaluated aboard the aircraft.
The unmanned plane, also known as Orbital Test Vehicle, or OTV, is 29 feet (9 meters) long, while the wingspan is spread across 15 feet. This makes it about one quarter of the size of the retired space shuttles of the National Aeronautics and Space Administration.
The X-37B made its first flight in April 2010 and it landed back after eight months. In March 2011, a second mission was launched and it lasted 15 months. In December 2012, a third flight took place made a comeback 22 months later.
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The X-37B’s latest landing was first in Florida, with the previous landings taking place at Vandenberg Air Force Base in California. In 2014, the US Air Force relocated the program and took over two of NASA’s former shuttle-processing hangars.
The fifth X-37B mission is likely to be launched from Cape Canaveral Air Force Station, located south of the Kennedy Space Center, later this year.