COLORADO SPRINGS, Colo.—The Space Development Agency (SDA) in late May plans to begin gathering test data from four L3Harris Technologies
[LHX] satellites the agency launched in February as part of a demonstration constellation for the Proliferated Warfighter Space Architecture (PWSA), SDA Director Derek Tournear said last week.
The L3Harris missile tracking satellites that are part of Tranche 0 of the PWSA are still going through testing and checkout, Tournear said on April 10 during a media briefing at the Space Symposium.
Last year, SDA launched four SpaceX-built Tranche 0 missile tracking layer satellites, which have provided “a lot of good data,” Tournear said.
Tranche 0 is the warfighter immersion tranche that will be used in military exercises and demonstrations to give warfighters a look at the capabilities that will be included in subsequent tranches, beginning with Tranche 1. In addition to the eight tracking layer satellites, Tranche 0 also includes 19 communications satellites on orbit, called the transport layer, 10 provided by Lockheed Martin [LMT] and nine by York Space Systems.
SDA is working with the Missile Defense Agency, which is adjusting some of its test launches so that SDA satellites will be overhead to gather data, Tournear said. This has not happened yet but is expected to happen in “single digit weeks,” he added. Every time a missile tracking satellite is over Space Stations in Vandenberg, Calif., or Cape Canaveral, Fla., SDA will be imaging because both these areas have “historically high missile activity,” he said.
It takes 40 tracking satellites to provide global coverage, Tournear said. The four SpaceX satellites offer 10 percent coverage of the Earth, “so, we don’t have great opportunity to catch a launch as a target of opportunity,” he said. The agency is also watching global hotspots for potential to see if the tracking satellites detect anything, he said.
Tournear was asked about a recent decision to not launch seven satellites being developed by RTX [RTX] for the Tranche 1 Tracking Layer. Space News reported in March that RTX’s work was being re-scoped and that the satellites would not be launched as part of the tranche.
Tournear said RTX realized that the scope of its work and the price it bid to win a share of the Tranche 1 Tracking Layer “wasn’t going to close” so the decision was made not to launch those satellites. Work is continuing under the contract to help reduce risk on Tranche 2, he said.
“There’s a lot of the components that are being developed on that Tranche 1 Tracking Raytheon contract that are flowing into some of the Tranche 2 vendors,” he said.
The Tranche 1 Tracking Layer vendors include Northrop Grumman [NOC] and L3Harris, which will each supply 14 satellites, which provides the minimum viable capability, Tournear said. The Tranche 2 Tracking Layer vendors are L3Harris, Lockheed Martin, and Sierra Space, which will each build 16 wide-field-of-view satellites for missile warning and tracking, and two medium-field-of-view satellites for missile defense.
The tracking and transport layer satellites for PWSA will operate in a low-Earth orbit.