Air Force's mystery mini-shuttle

A top-secret mini-space shuttle has blasted off from Cape Canaveral. The Air Force launched the unmanned spacecraft Dec. 11 aboard an Atlas V rocket.

FILE - This undated file image provided by the U.S. Air Force shows the X-37B spacecraft. The unmanned Air Force space plane steered itself to a landing early Saturday, June 16, 2012, at a California military base, capping a 15-month clandestine mission. (AP Photo/U.S. Air Force, File)
FILE - This undated file image provided by the U.S. Air Force shows the X-37B spacecraft. The unmanned Air Force space plane steered itself to a landing early Saturday, June 16, 2012, at a California military base, capping a 15-month clandestine mission. (AP Photo/U.S. Air Force, File)
FILE - This undated file image provided by the U.S. Air Force shows the X-37B spacecraft. The unmanned Air Force space plane steered itself to a landing early Saturday, June 16, 2012, at a California military base, capping a 15-month clandestine mission. (AP Photo/U.S. Air Force, File)
This Saturday, June 16, 2012 image from video made available by the Vandenberg Air Force Base shows an infrared view of the X-37B unmanned spacecraft landing at Vandenberg Air Force Base. The spacecraft, which was launched from Cape Canaveral Air Force Station in Florida in March 2011, conducted in-orbit experiments during the 15-month clandestine mission, officials said. It was the second such autonomous landing at the base. (AP Photo/Vandenberg Air Force Base)
This Saturday, June 16, 2012 image from video made available by the Vandenberg Air Force Base shows an infrared view of the X-37B unmanned spacecraft landing at Vandenberg Air Force Base. The spacecraft, which was launched from Cape Canaveral Air Force Station in Florida in March 2011, conducted in-orbit experiments during the 15-month clandestine mission, officials said. It was the second such autonomous landing at the base. (AP Photo/Vandenberg Air Force Base)
This Saturday, June 16, 2012 image from video made available by the Vandenberg Air Force Base shows an infrared view of the X-37B unmanned spacecraft landing at Vandenberg Air Force Base. The spacecraft, which was launched from Cape Canaveral Air Force Station in Florida in March 2011, conducted in-orbit experiments during the 15-month clandestine mission, officials said. It was the second such autonomous landing at the base. (AP Photo/Vandenberg Air Force Base)
Stretching 29 feet in length and weighing 11,000 pounds, the second Boeing-built X-37B became the longest on-orbit space vehicle on June 16, 2012 when it completed a 469-day mission with an autonomous landing at Vandenberg Air Force Station in
New Delay for Mysterious Military Space Plane Launch
Stretching 29 feet in length and weighing 11,000 pounds, the second Boeing-built X-37B became the longest on-orbit space vehicle on June 16, 2012 when it completed a 469-day mission with an autonomous landing at Vandenberg Air Force Station in
Designed to be launched like a satellite and land like an airplane, the second X-37B Orbital Test Vehicle, built by Boeing for the United States Air Force’s Rapid Capabilities Office, is an affordable, reusable space vehicle.
Launch of Air Force Secret Space Plane Delayed Again
Designed to be launched like a satellite and land like an airplane, the second X-37B Orbital Test Vehicle, built by Boeing for the United States Air Force’s Rapid Capabilities Office, is an affordable, reusable space vehicle.
A belly view of the U.S. Air Force's X-37B Orbital Test Vehicle as it sits inside its payload fairing during encapsulation at the Astrotech facility in Titusville, Fla., before its planned April 2010 launch.
Secretive X-37B Military Space Plane Launch May Be Delayed by Glitch
A belly view of the U.S. Air Force's X-37B Orbital Test Vehicle as it sits inside its payload fairing during encapsulation at the Astrotech facility in Titusville, Fla., before its planned April 2010 launch.
Technicians inspect the military X37-B space plane after its June 2012 landing, which completed the vehicle's second trip to orbit.
Secretive X-37B Military Space Plane Launch May Be Delayed by Glitch
Technicians inspect the military X37-B space plane after its June 2012 landing, which completed the vehicle's second trip to orbit.
This Saturday, June 16, 2012 image from video made available by the Vandenberg Air Force Base shows the X-37B unmanned spacecraft landing at Vandenberg Air Force Base. The spacecraft, which was launched from Cape Canaveral Air Force Station in Florida in March 2011, conducted in-orbit experiments during the 15-month clandestine mission, officials said. It was the second such autonomous landing at the base. (AP Photo/Vandenberg Air Force Base)
This Saturday, June 16, 2012 image from video made available by the Vandenberg Air Force Base shows the X-37B unmanned spacecraft landing at Vandenberg Air Force Base. The spacecraft, which was launched from Cape Canaveral Air Force Station in Florida in March 2011, conducted in-orbit experiments during the 15-month clandestine mission, officials said. It was the second such autonomous landing at the base. (AP Photo/Vandenberg Air Force Base)
This Saturday, June 16, 2012 image from video made available by the Vandenberg Air Force Base shows the X-37B unmanned spacecraft landing at Vandenberg Air Force Base. The spacecraft, which was launched from Cape Canaveral Air Force Station in Florida in March 2011, conducted in-orbit experiments during the 15-month clandestine mission, officials said. It was the second such autonomous landing at the base. (AP Photo/Vandenberg Air Force Base)

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