WASHINGTON — United Launch Alliance’s Vulcan Centaur rocket lifted off Aug. 12 from Space Launch Complex 41 at Cape Canaveral Space Force Station, carrying the U.S. Space Force’s USSF-106 mission. The launch marked Vulcan’s first flight for the National Security Space Launch program, a milestone that comes after years of development and certification delays.
Vulcan lifted off at 8:56 p.m. Eastern. The launch took place near the end of a one-hour launch window.
Vulcan is ULA’s next-generation launch vehicle, intended to replace both the Atlas 5 and Delta 4 families. The rocket’s first stage is powered by two BE-4 engines built by Blue Origin, fueled by liquid methane and liquid oxygen. Its Centaur V upper stage uses two Aerojet Rocketdyne RL10C engines burning liquid hydrogen and liquid oxygen.
For the USSF-106 mission, Vulcan flew for the first time with four solid rocket boosters, supplied by Northrop Grumman. These GEM 63XL boosters provided the extra thrust needed to send the payload directly into geostationary orbit, rather than the more common geostationary transfer orbit. The solids ignited alongside the BE-4 engines at liftoff and burned for nearly two minutes before separating.
Mission success
Approximately five minutes into the flight, ULA confirmed the Vulcan first stage had completed its burn and separated from the Centaur upper stage, followed moments later by the jettison of the rocket’s payload fairing. At the request of the Space Force, ULA ended the livestream after fairing separation.
The primary payload for USSF-106 is the Navigation Technology Satellite-3 (NTS-3), a $250 million experimental spacecraft developed by L3Harris for the Air Force Research Laboratory to test advanced positioning, navigation, and timing technologies from geostationary orbit. The Space Force did not disclose any additional payloads flying on this mission.
About eight hours after liftoff, the Space Systems Command confirmed the launch was successful.
“It’s an exciting day for us as we launched the first NSSL flight of Vulcan, an outstanding achievement for United Launch Alliance and the nation’s strategic space lift capability. This is an important milestone for the Space Force and all involved,” said Col. Jim Horne, USSF-106 mission director. “After years of development, technical collaboration, and dedication by all involved, including our government mission partners and the entire ULA team, I’m proud to say the first Vulcan NSSL mission delivered its payloads safely into space.”
This long-awaited launch begins Vulcan’s national security service at a time when the rocket has accumulated a backlog of more than two dozen NSSL assignments. Space Force officials say they expect ULA to work through the manifest in the coming years, restoring a two-provider posture alongside SpaceX for assured access to space.
The USSF-106 launch marks the Defense Department’s formal shift to flying national security payloads exclusively on U.S.-built rockets and engines, ending reliance on ULA’s Atlas 5, which used a Russian RD-180 main engine — a dependency the Pentagon moved to eliminate more than a decade ago by funding Vulcan’s development.
USSF-106 was Vulcan’s third flight.
Vulcan’s inaugural flight Jan. 8, 2024, known as Certification-1, launched from SLC-41 at Cape Canaveral. The mission carried Astrobotic’s Peregrine lunar lander under NASA’s Commercial Lunar Payload Services program, along with several secondary payloads. The BE-4–powered first stage and Centaur V upper stage performed as planned, but Peregrine suffered a propulsion system failure shortly after separation, preventing a lunar landing. Despite the payload issue, the mission successfully demonstrated Vulcan’s performance, completing the first step in Space Force certification.
The second Certification-2 mission Oct. 4, 2024, also flew from SLC-41 carrying an inert mass simulator and no operational spacecraft. The vehicle was powered by two GEM 63XL SRBs. One booster experienced a nozzle failure a little over 30 seconds after liftoff, causing asymmetric thrust. The mission nevertheless achieved its test objectives and completed the second certification flight. Subsequent updates pointed to a manufacturing defect in the SRB nozzle. Both certification flights provided data the Space Force used to certify Vulcan for NSSL missions in March 2025.