Gen. William Shelton said he expects a contract award for the Space Fence in April 2014. Credit: U.S. Air Force

WASHINGTON — The U.S. Air Force is hoping to bridge a potential gap in on-orbit space surveillance capabilities with a small satellite launching as soon as 2017 that would be developed by a rapid-response military space office that the service has proposed disbanding, a top Air Force officer said April 3.

Gen. William Shelton, commander of Air Force Space Command, told the House Armed Services strategic forces subcommittee that the Operationally Responsive Space (ORS)-5 mission also would act as a pathfinder for technologies to be used in a follow-on to the current Space Based Space Surveillance (SBSS) satellite.

Built by Boeing Space and Intelligence Systems of El Segundo, Calif., the SBSS satellite is part of a space situational awareness architecture that also includes ground-based radar and optical sensors. Ball Aerospace & Technologies Corp. of Boulder, Colo., was a major subcontractor on the SBSS satellite.

But the Air Force potentially faces a lengthy gap in capability once the current SBSS Block 10 satellite reaches the end of its lifetime, expected around 2017. A proposed follow-on satellite has been repeatedly delayed — the Air Force hopes to the start development in 2016 — and now will not launch before 2021 at the earliest.

Without some kind of gap filler, Shelton has said, the Air Force would be hard-pressed to keep tabs on threats to satellites in geosynchronous orbits. The ORS-5 mission would potentially plug that hole.

“Perhaps it’ll provide us a little bit of operational capability in the interim,” Shelton told SpaceNews after the hearing. “This will be a trailblazer so the development process here will be as quick as we can make it.”

The technologies demonstrated aboard ORS-5 could be applied to SBSS follow-on, Shelton added.

The Air Force’s 2015 budget request describes the ORS-5 mission as addressing “rapidly evolving threats and (to) serve as a pathfinder in this vital mission area.”

The Air Force is drawing funds for the project from the $96 million and $10 million appropriated by Congress in 2013 and 2014, respectively, for the Pentagon’s ORS Office at Kirtland Air Force Base, N.M. The Air Force has been seeking to dismantle that office and requested no funding for the office in 2015.

The SBSS Block 10 satellite, which officially began operations in April 2013, is designed primarily to keep tabs on the geostationary-orbit arc 36,000 kilometers above the equator, which is home to most communications satellites, both military and commercial. U.S. missile warning satellites operate in similar orbits.

The Air Force has long cited the need for a companion satellite for broader coverage, but the SBSS follow-on is now viewed as more of a replacement than a complement to the Block 10 satellite.

In 2012, the Air Force said it “accepts the risk” of a gap in its ability to keep tabs on objects in geosynchronous orbit. That scenario would become a reality if the SBSS Block 10 satellite fails before the follow-on satellite is launched, but Shelton has said Air Force satellites traditionally last longer their life expectancy.

U.S. defense officials have warned in recent years of growing threats to U.S. space assets, including those in geostationary orbit, but have declined to provide specifics.

Mike Gruss covers military space issues, including the U.S. Air Force and Missile Defense Agency, for SpaceNews. He is a graduate of Miami University in Oxford, Ohio.