Space Force’s secretive X-37B space plane soars past 1 year in orbit

That U.S. Space Force X-37B Orbital Test Vehicle (OTV-7) has silently slipped past one-year of flight time.

The craft is engaged in performing aerobrake maneuvers, a technique to alter its orbit around Earth, as well as safely dispose of its attached service module.

Lofted in December of 2023, the military spaceplane was placed in an orbit higher than any of the earlier space plane missions – into a highly elliptical high Earth orbit.

From that orbit, the United States Space Force, supported by the Air Force Rapid Capabilities Office, conducted radiation effect experiments and tested Space Domain Awareness technologies.

X-37B/OTV-7 is also referred to as United States Space Force-52 (USSF-52). This spaceplane was lofted on Dec. 28, 2023.

The OTV-7 flight marks the first time the U.S. Space Force and the X-37B have attempted to carry out a dynamic aerobraking maneuver.

Expending minimal fuel

In a statement released last year by Boeing, builder of the X37B “will perform ground-breaking aerobraking maneuvers to take the dynamic spaceplane from one Earth orbit to another while conserving fuel. Partnered with the United States Space Force, this novel demonstration is the first of its kind.”

The use of the aerobraking maneuver requires the heat-tiled spacecraft to conduct a series of passes using the drag of Earth’s atmosphere. That technique enables the spacecraft to change orbits while expending minimal fuel.

There are no details as yet on whether the X-37B’s aerobrake maneuvering is complete.

If so, the uncrewed vehicle was slated to resume its test and experimentation objectives until they are accomplished.

At that point, the vehicle is to de-orbit and execute a safe return to Earth, likely at the Kennedy Space Center Shuttle Landing Facility Runway.

Flight log

• OTV-1: launched on April 22, 2010 and landed on December 3, 2010, spending over 224 days on orbit.
• OTV-2: launched on March 5, 2011 and landed on June 16, 2012, spending over 468 days on orbit.
• OTV-3: launched on December 11, 2012 and landed on October 17, 2014, spending over 674 days on-orbit.
• OTV-4: launched on May 20, 2015 and landed on May 7, 2015, spending nearly 718 days on-orbit.
• OTV-5: launched on September 7, 2017 and landed on October 27, 2019, spending nearly 780 days on-orbit.
• OTV-6: launched on May 17, 2020 and landed on November 12, 2022, spending 908 days on-orbit.
• OTV-7: launched on December 28, 2023 and remains in-flight.

Leonard David is an award-winning space journalist who has been reporting on space activities for more than 50 years. Currently writing as Space.com’s Space Insider Columnist among his other projects, Leonard has authored numerous books on space exploration, Mars missions and more, with his latest being “Moon Rush: The New Space Race” published in 2019 by National Geographic. He also wrote “Mars: Our Future on the Red Planet” released in 2016 by National Geographic. Leonard  has served as a correspondent for SpaceNews, Scientific American and Aerospace America for the AIAA. He has received many awards, including the first Ordway Award for Sustained Excellence in Spaceflight History in 2015 at the AAS Wernher von Braun Memorial Symposium. You can find out Leonard’s latest project at his website and on Twitter.