Space Force seeks orbital-refueling tech in new budget

The Space Force is launching an effort to develop technology to refuel and maintain satellites, the service’s top officer said in an interview. 

“We're investing in demonstrations and capabilities to start to explore what you would need on orbit to be able to service and maintain satellites. This gives us some opportunities to explore dynamic maneuvering [and] maneuver without regret. These are things that will make our satellites harder to target, more defensible,” Chief of Space Operations Gen. Chance Saltzman said as part of Defense One’s State of Defense series. 

The service needs to develop on-orbit servicing because satellites with short lifespans and fixed fuel tanks are constraining operations, officials have said. The Space Force is asking for $20 million in its 2025 budget request to start developing tools to handle a new mission set called “Servicing, Mobility, and Logistics,” according to budget justification documents. Commercial services and technology will play a role, the documents say.

Among the “technical hurdles” is ensuring that such orbital services can be delivered to various types of satellites, Saltzman said.

“I hear a lot of chatter and industry talking about standards, and how to cooperate to make sure that a maintenance satellite can work with any of the satellites that we put on orbit so that you get that collaborative crossflow across industry,” he said. 

Saltzman suggested that the first satellites that can be serviced in orbit might launch in three to five years.

“You're probably not going to see anything, at least from a military standpoint, for a few years because the satellites that we have, that are going to launch in the next two to three years, have already been built, already being developed, are already past their design point, and so you've got to wait for the next design cycle to really start to add those capabilities in,” he said. 

Defense One spoke with Saltzman just after the Pentagon released its $849.8 billion funding request for fiscal 2025. The Space Force’s budget, which has steadily grown during its first four budget cycles, is decreasing this year: the service is requesting $29.4 billion in 2025, $600 million below last year’s request. 

Several factors depressed the top line, Saltzman said, including a reduction in planned satellite launches. 

“In this case, there was about $600 million in reductions in the number of launches that we required, because payloads weren’t ready or the manifest didn’t support [it]—again, any number of reasons why that would be the case,” Saltzman said. 

The 2025 spending proposal calls for 11 launches, down from the 15 once planned: $1.8 billion for seven launches through the National Security Space Launch program and $375 million for four launches for the Space Development Agency’s low-Earth orbit constellation.

The Pentagon had to build this year’s budget under Congress’s defense-spending cap, called the Fiscal Responsibility Act, which squeezed weapons programs across the department. The Air Force, for example, cut its planned buy of F-35 and F-15EX fighters to accommodate the cap. 

Saltzman declined to say how the cap affected specific Space Force programs, but said that caused “fiscal constraint” across the department. 

“We complied with it because it's the law of the land. We took the budgeting information we had and we built the programs as best we could,” he said.

Saltzman did say the cap will slow the service’s “counterspace effort,” the largely classified effort to develop capabilities to keep an enemy from using space assets.

“This is the area where I wish we could go faster, but the constraints have laid out so that we're not going to be able to go as fast as we can. We're still investing in those capabilities, maybe just not as quickly as we otherwise could,” he said. 

Most of the service’s 2025 budget would go toward research and development: $18.7 billion, down from last year’s request of $19.2 billion.

Despite budget constraints, Saltzman said they still were able to put money towards key efforts such as “resilient architectures”—for instance, orbiting more satellites to enable systems to work even if some are disabled by enemy action. 

The service wants to spend $4.7 billion on missile warning and tracking satellites in multiple orbits. This includes $2.6 billion for the Resilient Missile Warning and Tracking program and $2.1 billion for the Next-Generation Overhead Persistent Infrared program, or Next-Gen OPIR. 

“We are still investing heavily in resilient architectures to make sure that we can continue to provide missile warning, satellite communications, precision, navigation and timing when the nation needs it. We've invested heavily in our operational test and training infrastructure to make sure that our guardians have the kind of advanced training that they need for the threats they're going to face. And so there's lots of areas that I feel very comfortable that we've plus-ed up and that we're increasing to make sure we can meet all the requirements of the National Defense Strategy,” Saltzman said.