LaunchesSDA Tranche 1 Transport Layer B
SpaceXSUCCESS

SDA Tranche 1 Transport Layer B

Falcon 9 · Government/Top Secret

Sep 10, 2025 · 14:12 UTCSpace Launch Complex 4E, Vandenberg

Mission

Tranche 1 Transport Layer B is one of six missions by the United States Space Force Space Development Agency (SDA) for the Proliferated Warfighter Space Architecture (PWSA) Tranche 1 Transport Layer constellation, which will provide assured, resilient, low-latency military data and connectivity worldwide to the full range of warfighter platforms from Low Earth Orbit satellites. The constellation will be interconnected with Optical Inter-Satellite Links (OISLs) which have significantly increased performance over existing radio frequency crosslinks. It is expected to operate over Ka band, have stereo coverage and be dynamically networked for simpler hand-offs, greater bandwidth and fault tolerance. This launch carries 21 satellites manufactured by York Space Systems.

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Mission Facts

Provider
SpaceX · SDA
Rocket
Falcon 9
Orbit
PO
Pad
Space Launch Complex 4E
NET precision
Second
Data source
LL2
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