While the U.S. Space Force’s first Space Warfighting Framework, released last month, highlights the importance of satellite maneuver to complicate adversary surveillance and targeting, in-space refueling to ease such maneuver is not a done deal for the service.
U.S. Space Command “usually talks about dynamic space operations [DSO], which is much bigger than just refueling,” Lt. Gen. Shawn Bratton, the Space Force’s deputy chief of space operations for strategy, plans, programs, and requirements, told a Mitchell Institute for Aerospace Studies’ virtual forum on Thursday.
DSO includes in-space refueling, on-orbit repair/upgrades, satellite maneuver among orbits, and rapid launch/deployment of cheaper satellites.
“Those concepts of movement and maneuver are built into the concept of dynamic space operations,” Bratton said. “We’re trying to understand the value proposition of refueling and the trades that come with it. We are investing in demonstration of capability. We’ve got some studies going on with some of our teammates who are peeling this apart on the cost side and the military advantage. That’s really what I’m trying to understand–mostly in my S-5 hat on setting the force design–what’s the military advantage of refueling? It’s very clear in the air domain when you refuel an airplane. It extends the range of the aircraft to reach targets you otherwise couldn’t.”
“It’s a different use case on orbit, and mainly we’re talking about GEO [geosynchronous orbit],” Bratton said. “With refueling, you can get more use out of the spacecraft maybe. Sometimes it could extend the life of the spacecraft, but I don’t think that’s the main use case. Usually, other components will fail on a spacecraft over time. And so, if that [enhanced satellite use/life extension] is the advantage that refueling brings, let’s put that into some war gaming, run it through a conflict. How much of a difference does going to war with [satellite] refueling or without refueling make, and how do I quantify that advantage? Then we can measure that against the budget choices we gotta make. We’re in the middle of that work within the service right now.”
Bratton said that he expects to have the data this fall on satellite refueling and the opportunity costs of pursuing it to present to Chief of Space Operations Gen. B. Chance Saltzman and Air Force Secretary Troy Meink.
Space Force’s Geosynchronous Space Situational Awareness Program (GSSAP) is one example of future tradeoff considerations for the service. Five of six Northrop Grumman [NOC]-built GSSAP satellites are still in operation. Four were launched between 2014 and 2016, and two in January 2022. The satellites maneuver to conduct rendezvous and proximity operations to monitor and inspect other satellites.
The Department of the Air Force is examining the insertion of commercial features in GSSAP to reduce cost and construction times (Defense Daily, May 14).
“Of those use cases, GSSAP’s a great example” of refueling tradeoffs, Bratton said. “Is there enough of that out there where now I’ve got to sort out a refueling infrastructure and defend it, or do I go to a smaller, proliferated GSSAP that maybe are lower cost and easier to get on orbit, and I just use a replenishment strategy rather than refueling. I think there’s a place for refueling at some point in the future is sort of where I’m landing right now. We’ll see how far in the future. Is it we need this in [a] three-year, five-year, or 10-year time horizon?
Northrop Grumman, Astroscale U.S., a subsidiary of Japan’s Astroscale, Arcfield‘s Orion Space Solutions/Redwire Corp. [RDW], and Lafayette, Colorado-based start-up Orbit Fab are to demonstrate satellite refueling for Space Force (Defense Daily, Apr. 2).
Space Force is to demonstrate Northrop Grumman’s refueling payload on the service’s Tetra-6 mission in 2027.
In February, Redwire said that it had received a contract from Arcfield’s Orion Space Solutions to build a Mako satellite to support the Tetra-6 mission to demonstrate different refueling methods for geosynchronous orbit satellites; cooperative and prepared inspection; docking; proximity operations; autonomy techniques to enable future on-orbit servicing; and sustained space maneuver.
Redwire is also building two Mako platforms for Tetra-5, which was on track for this year, but is now scheduled for June next year.
Last August, Orbit Fab said that SSC had qualified the company’s Rapidly Attachable Fluid Transfer Interface (RAFTI) as a refueling interface for in-space refueling of military satellites.
“Orbit Fab has priced the RAFTI refueling port at $30,000 to make it easily accessible for missions of all sizes,” the company said.
In January last year, Astroscale U.S. said that it had received a nearly $26 million award from Space Force to deliver the Astroscale Prototype Servicer for Refueling (APS-R) satellite by next year. APS-R, which will use Orbit Fab refueling interfaces, is to provide on-demand hydrazine to increase satellite mobility.