Mysterious X-37B Military Space Plane Nears 1 Year in Orbit

The U.S. Air Force's X-37B miniature space plane has winged past 340 days in orbit performing secretive duties during the program's fifth flight.

The robotic craft's latest mission, known as Orbital Test Vehicle-5 (OTV-5), kicked off on Sept. 7, 2017, with a launch atop a SpaceX Falcon 9 rocket from NASA's Kennedy Space Center (KSC) in Florida.

As usual, Air Force officials have revealed few details about OTV-5. But we do know that one payload flying aboard the X-37B this time around is the Advanced Structurally Embedded Thermal Spreader, or ASETS-11. Developed by the U.S. Air Force Research Laboratory, this cargo is testing experimental electronics and oscillating heat pipes for long durations in the space environment.

The classified X-37B program "fleet" consists of two known reusable vehicles, both of which were built by Boeing. Looking like a miniature version of NASA's now-retired space shuttle orbiter, the military space plane is 29 feet (8.8 meters) long and 9.6 feet (2.9 m) tall, with a wingspan of nearly 15 feet (4.6 m).

The X-37B has a payload bay about the size of a pickup-truck bed, which can be outfitted with a robotic arm. The space plane has a launch weight of 11,000 lbs. (4,990 kilograms) and is powered on orbit by gallium-arsenide solar cells with lithium-ion batteries.

• Each X-37B mission has set a new flight-duration record for the program:
• OTV-1 began April 22, 2010, and concluded on Dec. 3, 2010, after 224 days in orbit.
• OTV-2 began March 5, 2011, and concluded on June 16, 2012, after 468 days on orbit.
• OTV-3 chalked up nearly 675 days in orbit before finally coming down on Oct. 17, 2014.
• OTV-4 conducted on-orbit experiments for 718 days during its mission, extending the total number of days spent in space for the OTV program to 2,085 days.

How long OTV-5 will stay aloft is unknown. Whenever it comes down, the robotic vehicle is likely to land at ...Read More HERE

[The X-37B Space Plane: 6 Surprising Facts]