SDA must be ‘more realistic’ about real risks in pricey satellite Tracking Layer effort: GAO

WASHINGTON — The Space Development Agency’s (SDA) program to develop a Tracking Layer constellation of missile warning/tracking satellites in low Earth orbit (LEO) is in danger of failing to meet both its own goals and the needs of operators, according to a new report by the Government Accountability Office (GAO).

The report, “Missile Warning Satellites: Space Development Agency Should Be More Realistic and Transparent About Risks to Capability Delivery,” was released today, based on a review by the congressional watchdog office of SDA’s Tracking Layer activities between October 2023 and January 2026. While the report is specific to the Tracking Layer, GAO finds that many of the problems plaguing that project also cut across SDA’s overarching effort to build a network of LEO constellations for its Proliferated Warfighter Space Architecture (PWSA), which also includes the Transport Layer of data relay satellites and ground systems.

GAO asserts that SDA “is overestimating the technology readiness of some critical elements it plans to use.” This includes the spacecraft being developed and operated by multiple vendors, which GAO says have needed modifications that “required additional unplanned work” by contractors and “added to already delayed schedules.”

Perhaps most significantly, the report finds that SDA and its contractors “have yet to demonstrate the development of timely, actionable, and accurate two-dimensional tracks on orbit and three-dimensional tracks on the ground needed to counter hypersonic and other evolving threats.”

While the report says that SDA reports “achieving early milestones” as it moves ahead every two years with new satellite variants called Tranches, those reports “do not reflect schedule risks” and the agency has not “developed an overall or architecture-level schedule” that could allow a better understanding of progress.

As of July 2025, the report notes, SDA to awarded contracts worth $4.7 billion for 101 satellites in Tranche 0, 1 and 2 of the Tracking Layer to six prime contractors: L3Harris Technologies, Lockheed Martin, Northrop Grumman, Raytheon, Sierra Space and SpaceX. In December, the agency issued four more contracts, worth a total of $3.5 billion for a total of 72 Tranche 3 satellites, to teams led by Lockheed Martin, Rocket Lab USA, Northrop Grumman, and L3Harris.

In addition, the report stresses that the Tracking Layer satellites are expected to have only a five-year lifetime, at which point SDA will need to replace them — the cost of which has not yet been defined.

“[T]he Department of Defense (DOD) does not know the life-cycle cost to deliver missile warning and tracking capabilities because it has not created a reliable cost estimate,” GAO chides.

Finally, the report states that SDA’s requirements process is not transparent, including to operators who are supposed to use the Tracking Layer constellation.

“For example, SDA is not sufficiently collaborating with combatant commands, which report having insufficient insight into how SDA defines requirements and when, or whether, SDA will deliver planned capabilities. Consequently, SDA is at risk of delivering satellites that do not meet warfighter needs,” the report says.

GAO makes six recommendations for action by the Office of the Secretary of the Air Force, which oversees SDA acquisition and budget plans, for improving the situation:

• Ensure that SDA “conducts and documents a tailored technology readiness assessment for new critical technology elements inserted in each future tranche,” starting with Tranche 3 which is expected to start launching in the fourth quarter of 2029.
• Ensure the agency is following the process set out in its Warfighter Council charter “to collaboratively, with warfighter participants, identify, define, and prioritize requirements, and present regular opportunities for interactive feedback and warfighter response.”
• Ensure SDA is able to trace back “between overall mission warning and mission tracking requirements and tranche development efforts.”
• Ensure SDA “develops and maintains an architecture-level networked schedule” for the overarching PWSA “that reflects both government and contractor activities.”
• Require the agency to mandate that contractors provide “Cost and Software Data Reporting.”
• Ensure SDA “develops and establishes reliable, data-driven cost estimates and a process for regularly updating these estimates that supports cost-informed decision-making beginning with Tranche 3.”

In a letter to GAO from then-acting head of Air Force space acquisition Maj. Gen. Stephen Purdy dated Dec. 16, the Pentagon concurred with five of the recommendations and partially concurred with one — commenting that SDA already is complying with Department of the Air Force requirements for Cost and Software Data Reporting and will continue to do so.

A spokesperson for SDA did not immediately respond to a request for comment for this report.