The Air Force is poised to launch an unmanned winged spacecraft resembling a miniature space shuttle this week — and it probably won't be a one-time shot.
Gary Payton, Air Force deputy under secretary for space programs, said Tuesday that the Air Force has contracted for a second space plane depending on the success of the prototype's maiden flight.
While in orbit, the X-37B Orbital Test Vehicle will conduct classified technology experiments.
The spacecraft is slated to launch Thursday from Florida — somewhat later than the original plan for a Monday launch. Officials delayed the X-37B liftoff when NASA extended Discovery's mission by one day, which put the shuttle landing on Monday as well.
Typically, two days between shuttle landings and rocket launches are required in order to reset the Eastern Range, which NASA shares with the nearby Cape Canaveral Air Force Station, for new space missions.
Air Force officials have shared few details of the upcoming X-37B test flight, an orbital debut for the reusable space plane.
"The first mission will emphasize proving technologies necessary for long duration reusable space vehicles with autonomous re-entry and landing capabilities," Air Force spokeswoman Angie Blair told Space.com.
The X-37B can stay in orbit for up to nine months. It will autonomously glide back to Earth and land on a runway in California.
According to released specifications, the space plane weighs about 11,000-pounds and is just over 29 feet in length. It stands slightly more than 9 1/2 feet in height and has a wingspan just over 14 feet across.
The spacecraft originally began its life as a NASA X-37 project to develop a new generation of reusable spacecraft. NASA shuttered the project in 2004 when funding dried up and turned the space plane over to the Defense Advanced Research Projects Agency.
The Air Force took control of the prototype in 2006, though exactly what the X-37B will do on its first mission – dubbed Orbital Test Vehicle 1 (OTV-1) – remains a mystery.
Some outside observers have said the Air Force's upcoming test launch could be seen by other countries as another push by the United States into the possible weaponization of space. Others, however, contend that the results of the X-37B's debut spaceflight could lead to better commercial space planes in the future.
Mark Sirangelo, corporate vice president of space systems for the commercial spaceflight company Sierra Nevada Corp., has said the Air Force's test flight is of great interest to his company. Sierra Nevada is developing a commercial space plane called Dream Chaser, which is also designed to launch atop an Atlas rocket.
"We expect that this [X-37B] launch experience will also help our knowledge of the Atlas's performance relative to lifting body vehicles," Sirangelo told Space.com in a recent interview. "The X-37 seems to be focused on military needs and is an unmanned demonstration while we are focusing primarily on a crewed civil and commercial mission profile."
The Associated Press and Space.com contributed to this report.