SpaceX launched the final GPS III satellite for the U.S. Space Force on Tuesday, April 21, 2026, at 2:53 a.m. EDT from Cape Canaveral Space Force Station, marking the end of a multiyear effort to modernize the nation’s navigation constellation.
The Falcon 9 rocket carried GPS III SV10, also known by the ceremonial name “Hedy Lamar,” into medium Earth orbit approximately 90 minutes after liftoff. This satellite is the tenth and last in the GPS III series, which delivers three times the positional accuracy and eight times the jam resistance of legacy GPS systems, according to Space Force officials.
The mission almost didn’t fly on a SpaceX rocket. Originally slated for launch on United Launch Alliance’s Vulcan Centaur vehicle, the satellite was switched to a Falcon 9 last month after recurring issues with the Vulcan’s solid rocket boosters delayed its readiness. As part of the swap, Vulcan Centaur will now launch the USSF-70 national security mission, currently scheduled for no earlier than summer 2028.
The Falcon 9 booster used for this flight, tail number B1095, completed its seventh launch and landing, having previously supported six Starlink missions. It touched down on the drone ship “Just Read the Instructions” about 8.5 minutes after liftoff, marking the final recovery for that vessel before it is reassigned to support SpaceX’s Starship program.
Both halves of the payload fairing were also recovered after splashdown, with one half flying for the second time — having been used on the GPS III-9 mission in January. Anne Mason, director of SpaceX’s National Security Space Launch division, noted the reuse offered meaningful assurance benefits for the mission.
Weather played a role in the timeline. A previous attempt on April 20 was scrubbed due to unfavorable conditions in the booster recovery zone, but forecasters predicted a 90 percent chance of favorable conditions for the April 21 window, with only minor risks from scattered or thick clouds.
For more on this story, see SpaceX Falcon 9 to Launch Cygnus XL Resupply Mission to ISS.
For observers along Florida’s Treasure Coast, the launch was visible under clear skies, with potential sightings reported as far north as Jacksonville Beach and as far south as Fort Pierce and West Palm Beach, depending on cloud cover and trajectory.
USSF Col. Stephen Hobbs, commander of Mission Delta 31, called the launch a milestone, noting that while the GPS III block is complete, it serves as a foundation for the upcoming GPS IIIF generation, which promises further advances in capability for both military and civilian users worldwide.
How the rocket swap affects future national security launches
The shift of GPS III SV10 from Vulcan Centaur to Falcon 9 highlights ongoing reliability concerns with ULA’s new rocket, particularly its solid rocket boosters, which have delayed multiple national security missions. While Space Force officials expect the issues to be resolved by 2028, the delay pushes back the launch of USSF-70, a mission originally intended for a Falcon Heavy, now reassigned to Vulcan Centaur.
This follows our earlier report, Space Sustainability: Tackling Space Junk and Environmental Challenges.
What the reuse of flight-proven hardware means for mission cost and reliability
Flying a booster on its seventh mission and reusing a payload fairing half demonstrates SpaceX’s continued emphasis on flight-proven hardware to reduce costs and increase launch cadence. For national security missions, where mission assurance is paramount, the successful reuse of components that have flown before — like the fairing from the GPS III-9 launch — adds confidence without sacrificing new hardware where needed.
Why was the GPS III satellite switched from Vulcan Centaur to Falcon 9?
The switch was made due to persistent issues with the solid rocket boosters on United Launch Alliance’s Vulcan Centaur rocket, which delayed its readiness for national security missions.
Is this the last GPS satellite ever to be launched?
No. While GPS III SV10 is the final satellite in the GPS III series, the Space Force is already developing the GPS IIIF generation, which will offer enhanced capabilities and begin launching in the coming years.
