SpaceX launched a series of new state-of-the-art satellites for the US Space Force on Sunday, April 2, after days of delays caused by the last-second outage last week. A Falcon 9 rocket carrying 10 spacecraft for the Space Development Agency (SDA) was launched from California’s Vandenberg Space Force Base at 10:29 am ET (14:29 pm GMT; 07:29 CST) on Sunday. The first-stage launch vehicle then returned to Earth and landed at Vandenberg 4’s landing site just eight minutes after takeoff.

“This was the second launch and landing for this particular launch vehicle and our 183rd successful launch of an orbital-class rocket,” SpaceX production engineer Jessie Anderson said during a live commentary. According to SpaceX’s mission statement, the rocket had previously helped launch a group of SpaceX’s Starlink internet satellites into orbit.

SpaceX did not show a live broadcast of Falcon 9’s second stage launch or payload shell detachment, as it stopped live broadcast shortly after the launch vehicle’s landing, at the Space Agency’s request.

SpaceX’s mission statement does not say when the Tranche 0 spacecraft is scheduled to be deployed. Details on national security missions like this are often difficult to come by. However, we do know something about the Tranche 0 spacecraft, for example they are the first members of the Progressive Warrior Space Architecture (PWSA), a constellation the SDA will assemble in low Earth orbit.

Air and Space Forces Magazine, about PWSA, “According to the plan, the Space Force will have hundreds of small satellites and new ones will be launched every few years to increase stability and capabilities in orbit.”