Sierra Space has successfully passed the Critical Design Review (CDR) for the missile-tracking satellites under the U.S. Space Development Agency’s (SDA) Tranche 2 Tracking Layer (T2TRK) program. This milestone clears the way for the company to begin full production of advanced satellite systems tailored for missile warning and defense missions.

Under the contract, Sierra Space is slated to deploy eighteen satellites across two orbital planes. Each satellite will carry infrared sensors dedicated to detecting and tracking ballistic, hypersonic, and emerging threat types. The architecture is structured to form a resilient detection network, with multiple sensors per plane—including missile defense sensors—ensuring continuous coverage even under duress.

With design review now complete, Sierra Space will move into the assembly, integration, and testing stages of T2TRK. According to the release, hardware has already begun arriving at its primary manufacturing facility, known as Victory Works. The company intends to leverage high-rate production methods to deliver its “Horizon” class spacecraft rapidly and reliably.

Sierra Space frames this achievement as a demonstration of its ability to combine commercial agility with deep domain expertise in space systems. Over its decades-long history, it has participated in more than 500 missions and accumulated 30+ years of spaceflight experience, positioning it to support U.S. Department of Defense and allied national security objectives.

Erik Daehler, Senior Vice President of Sierra Space Defense, stated that the successful CDR confirms the company’s readiness to deliver sophisticated solutions aligned with the SDA’s vision. He emphasized that the firm is committed to fielding systems purpose-built for countering evolving threats in space.

Looking ahead, Sierra Space will continue pushing through integration and testing phases while positioning itself as a leading supplier of space-based defense assets. The T2TRK constellation is a key element of the Proliferated Warfighter Space Architecture (PWSA), intended to bolster missile warning, tracking, and defense capabilities for U.S. and partner forces.