United Launch Alliance (ULA) is poised to mark a significant milestone in its history with the upcoming launch of its Vulcan rocket, which has recently been certified to carry national security payloads for the United States government.
The 202-foot-tall (61 m) Vulcan rocket is set to launch a pair of satellites as part of the United States Space Force (USSF)-106 mission.
Gary Wentz, vice president of Government and Commercial Programs for ULA, explained during a prelaunch teleconference that this mission is particularly significant as it will head directly to geosynchronous orbit, representing one of the company’s longest missions to date.
“This was purposefully designed to support these missions, direct inject to GEO for the Space Force. This is our 101st mission for national security space, and we’re proud to deliver the majority of our country’s critical satellites to orbit,” he said.
On the day of the launch, ULA transported the Vulcan rocket approximately a third of a mile from the government Vertical Integration Facility (VIF-G) to the pad at Space Launch Complex 41, a process that took a little over an hour from the start of the move to the rocket being secured at the launch pad.
Live coverage of the launch will be available through Spaceflight Now, starting approximately 1.5 hours prior to the scheduled liftoff at 7:59 p.m. EDT (2359 UTC).
In addition to the Vulcan rocket’s launch, coverage will also include the countdown and launch for Arianespace’s Ariane 6 rocket, which has a precise launch time of 8:37 p.m. EDT (0037 UTC).
The 45th Weather Squadron has anticipated an 80 percent chance of favorable conditions during the hour-long launch window, although cumulus clouds and solar activity may present complications.
The upcoming USSF-106 mission marks ULA’s strategic return to launches associated with the National Security Space Launch (NSSL) program, following its last such mission a little over a year ago on July 30, 2024, which used the Atlas 5 rocket.
This return to national security payloads arrives after the U.S. government mandated that domestic launch providers move away from reliance on Russian-made engines post-Russia’s initial invasion of Ukraine, prompting ULA to develop its Vulcan rocket as an American-designed solution.
Col. James Horne expressed excitement about this milestone, stating it marks the official end of U.S. reliance on Russian-made engines.
“We officially end our reliance on Russian-made engines with this launch, and we continue to maintain our assured access to space with at least two independent rocket service companies that we can leverage to get our capabilities in orbit,” Horne said.
However, getting Vulcan authorized for flight was not without its challenges. A notable anomaly in the second certification flight in October 2024 delayed the completion of certification for NSSL missions for several months.
Horne detailed that ULA and Northrop Grumman collaborated closely to address the issue, undergoing numerous static fire tests, extensive sub-scale analyses, and modeling processes to reach an acceptable risk level for the upcoming launch.
“So, we certified the design of the vehicle in March and then we worked through our mission-specific risk analysis to get to launch on Tuesday,” he remarked.
Horne noted that the Space Force closely evaluated several components of the Vulcan rocket, particularly the two Blue Origin-built BE-4 engines that power the rocket at liftoff since this was their first flight in the Vulcan configuration.
“We think we got excellent data from Cert-2 that showed just how capable of an engine that is with its ability to overcome the issue we saw with the solid rocket booster,” Horne added.
He mentioned that while the Vulcan is now certified to carry what he described as “A and B missions,” the Space Force is still in the process of certifying the heavier version of the Vulcan that incorporates six solid rocket boosters.
The first heavy launch for ULA is expected to be for Amazon’s Project Kuiper constellation, which will see the deployment of 45 broadband satellites into low Earth orbit.
Despite this launch contributing to certification for the heavier variant, additional analysis and certification tasks will still be necessary before full approval.
Horne shared that after completing the USSF-106 mission, ULA’s upcoming NSSL launch will be USSF-87, although an exact date has yet to be scheduled.
The USSF-106 mission comprises two satellites, one of which remains classified. The known primary payload is the Navigation Technology Satellite-3 (NTS-3), developed by the Air Force Research Laboratory (AFRL).
Dr. Joanna Hicks, a senior research aerospace engineer within the AFRL’s Space Vehicles Directorate and the principal investigator for NTS-3, expressed enthusiasm for the project.
“This is the first experimental navigation satellite in 48 years. The last one was NTS-2 that launched in 1977,” Hicks explained. “We think that we are overdue for an experiment in this area. GPS is such an integral part of our lives today… and with NTS-3, we are going to be experimenting with a number of different technologies to continue evolving and augmenting GPS to ensure that it remains the gold standard that our warfighters need.”
Once NTS-3 is deployed from Vulcan’s Centaur upper stage, it will undergo a couple of weeks of checkouts and commissioning on orbit before commencing its operational tasks.
The satellite is anticipated to conduct over 100 Positioning, Navigation, and Timing (PNT) experiments aimed at augmenting the existing GPS system.
These experiments will include improved time-keeping methodologies and the testing of an electronically steerable phased array antenna, which Hicks noted would assist in delivering higher power to counteract interference.
Additionally, the Chimera project, part of the experiments, aims to jointly authenticate satellite orbit data and measure the distance between the satellite and the user, providing robust protection against GPS spoofing for civil users.
Hicks remarked, “As a reprogrammable architecture, we don’t have to have everything planned out before we go on orbit and observe emerging threats. This capability extends beyond the satellite, as we will pair it with reprogrammable user equipment able to receive new signals defined even after launch.”
L3Harris Technologies served as the prime contractor for the NTS-3 satellite, building on Northrop Grumman’s ESPAStar satellite bus.
In 2018, L3Harris was awarded an $84 million contract, and the satellite passed its critical design review in 2020.
The initial launch date was anticipated for 2022, but unforeseen delays caused the satellite’s delivery to be postponed until January 2023, which pushed back the launch schedule.
Andrew Builta, vice president of Strategy and Business Development at L3Harris Technologies, explained their role in the project’s success.
“L3Harris has been responsible for the design, development, integration, and testing of the space vehicle,” Builta stated. “We also developed a portion of the ground control segment and supported launch vehicle integration, alongside integration with the control and user segments, and will assist in on-orbit operations.”
The various tests associated with the NTS-3 mission are designed to be conducted in both laboratory and field environments.
Hicks noted that insights gained from these experiments, such as calibrating a spot beam antenna, could be applied to the next generation of GPS satellites being developed by Lockheed Martin, known as GPS 3-F.
She elaborated, “One of the things that NTS-3 is testing… is the multi-orbit constellation concept, allowing us to receive signals from both NTS-3 at GEO and GPS at MEO (medium Earth orbit) to exploit the benefits of both systems. While it is not currently planned, we could envision deploying some of these technologies in LEO in the future.”
The upcoming launch of the USSF-106 mission showcases the ongoing collaboration and innovative spirit within the aerospace industry as it seeks to advance critical technologies that will underpin U.S. national security operations in space.
image source from：spaceflightnow
