Air Force space plane in Earth orbit for over 666 days.
Credit: Boeing/Inside Outer Space Screen Grab

The puzzling and classified U.S. Air Force X-37B space plane appears ready to set a new milestone in its hush-hush current mission: Breaking a new long-duration record in circling the Earth.

Also tagged as the Orbital Test Vehicle (OTV) – 5 mission, this space plane was lofted into low Earth orbit back on September 7, 2017.

Hurled skyward atop a SpaceX Falcon 9 booster from Launch Complex 39A at NASA’s Kennedy Space Center in Florida, the space plane is approaching a milestone for the program.

OTV-5 test image taken June 29.
Credit: Ralf Vandebergh

Last and lengthiest

The last and lengthiest Air Force’s X-37B mission, OTV-4 — after 718 days of flight — touched down at NASA’s Kennedy Space Center Shuttle Landing Facility May 7, 2017 – a first for the program. All prior missions had ended with a tarmac touchdown at Vandenberg Air Force Base in California.

“It is our goal to continue advancing the X-37B OTV so it can more fully support the growing space community,” said Randy Walden, the director of the Air Force Rapid Capabilities Office in a statement about the current spacecraft in orbit,” he said.

X-37B handout.
Credit: Boeing

New flight-duration record

Each X-37B/OTV 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 at that point to 2,085 days. It was launched in May 2015 and landed in May 2017.

The X-37B Orbital Test Vehicle mission 4 (OTV-4), the Air Force’s unmanned, reusable space plane, landed at NASA’s Kennedy Space Center Shuttle Landing Facility May 7, 2017.
Credit: USAF

Adversaries don’t know

It is always touch and go regarding what can/cannot be said about the space plane program.

However, former Secretary of the Air Force Heather Wilson laid out some basic details of the X-37B’s mission during an appearance at the Aspen Security Forum last month.

“The Air Force has acknowledged that we own a space plane, the X-37 – looks like a small version of the shuttle, but it’s unmanned. One of the things that’s fascinating about that space plane is that it can do an orbit that looks like an egg, and when it’s close to the Earth it is close enough to the atmosphere to turn where it is, which means our adversaries don’t know – and that happens on the far side of the Earth from our adversaries – they don’t know where it’s going to come up next, and we know that drives them nuts,” Wilson said.

Last Air Force’s X-37B Orbital Test Vehicle mission touched down at NASA ‘s Kennedy Space Center Shuttle Landing Facility May 7, 2017.
Credit: Michael Martin/USAF

Observing orbits

Ted Molczan is a Canada-based amateur astronomer who specializes in observing satellites and analyzing their orbits.

In commenting on Wilson’s statement: “The description is severely lacking in detail, but it appears to be of a maneuver made at the perigee of an elliptical orbit. The phrase ‘close enough to the atmosphere to turn where it is,’ suggests that the atmosphere plays some role in changing the orbital plane, Molczan told Inside Outer Space. “I am not familiar with maneuvers in the atmosphere, but I can comment on plane-changes, which consist of a change of inclination and/or longitude of the ascending node.”

Back to hangar for another flight day. U.S. Air Force X-37B/OTV-4 is rolled into facility after its May 7 landing at Kennedy Space Center.
Credit: Michael Martin/SAF

Satellite trackers

Molczan said his fellow sky watchers have tracked significant portions of all five X-37B missions to-date.

“We detected only circular orbits. Maneuvers consisted almost exclusively of changes of altitude. The few small plane changes that were detected did not disrupt tracking of the spacecraft. In some cases, it took weeks or months before we detected newly launched spacecraft in orbit. I doubt that large maneuvers occurred prior to our initial observations, but I cannot exclude the possibility,” Molczan said.

Tantalizing thought

Bottom line: Exactly when the OTV-5 space plane will land is unknown.

Meanwhile, a tantalizing thought: Could the program shoot for two X-37B vehicles in Earth orbit at the same time?

According to some launch websites, a United Launch Alliance Atlas 5 rocket will launch the AFSPC 7 mission for the U.S. Air Force this December. The mission’s primary payload is the X-37B, with liftoff from Cape Canaveral Air Force Station – SLC-41.

For more information on the X-37B project, go to:

Military Space Plane: Headed for New Record?

Also, go to this 8/5/2019 Defense News report at:

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