Seeking to close sensor tracking gaps against maneuvering hypersonic missiles throughout their entire flight envelopes, the Space Development Agency (SDA) issued a Request for Information (RFI) on Tuesday, October 20, 2026, to evaluate next-generation missile-tracking technologies for the Proliferated Warfighter Space Architecture (PWSA).

Released in support of the Space Force Portfolio Acquisition Executive for Missile Warning and Tracking, the solicitation asks defense industry contractors for technical enhancements to the low Earth orbit (LEO) Tracking Layer.

Dual-Track Acquisition and Demonstration Framework

The RFI outlines a dual-track procurement strategy designed to inform the upcoming Tranche 4 solicitation. SDA officials are weighing full-rate production contracts for Tranche 4 Tracking Layer satellites alongside separate partnership agreements for rapid prototyping and short-term on-orbit flight demonstrations. By testing experimental sensor payloads on dedicated demonstration platforms ahead of constellation integration, the agency aims to mature advanced detection concepts and reduce technical integration risks before committing to multi-spacecraft production runs.

Program Lineage and Tranche Evolution

The Tranche 4 initiative builds upon the agency’s two-year spiral development cycle, which fields successive generations of low Earth orbit spacecraft to pace emerging aerial threats. The solicitation follows extensive constellation procurement completed when the Space Development Agency awarded $3.5 billion for Tranche 3 missile tracking satellites in late 2025, followed by SDA awarding an additional $1.75 billion for 36 accelerated missile defense tracking satellites in July to support layered homeland defense architectures.

Full-Trajectory Sensor Architecture and Capabilities

Central to the technical inquiry is the integration of enhanced Missile Warning, Tracking, and Defense (MWTD) payloads capable of maintaining continuous track custody over advanced maneuvering targets. While earlier tranches emphasized initial launch detection and wide-area missile warning, Tranche 4 seeks infrared and electro-optical sensor payloads engineered to track hypersonic glide vehicles and cruise missiles across their full flight trajectories. These upgraded space vehicles will integrate optical inter-satellite links to route fire-control tracking data directly into the PWSA Transport Layer mesh network for rapid dissemination to tactical warfighters.

Procurement Timeline and Submission Deadlines

Industry responses to the Tracking Layer Tranche 4 RFI are due by December 4, 2026. Feedback gathered from the submissions will shape the formal Tranche 4 request for proposals and define the operational parameters for upcoming orbital prototype flight demonstrations scheduled toward the late 2020s.