Launch Success
Liftoff Time (GMT)
14:12:11
Wednesday September 10, 2025
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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.
Manufacturer: York Space Systems
Operator: Space Development Agency
Polar Orbit
21 Payloads
Agency
SpaceXPrice
$69.75 million
Rocket
Diameter: 3.7m
Height: 70m
Payload to Orbit
LEO: 22,800 kg
GTO: 8,300 kg
Liftoff Thrust
7,607 Kilonewtons
Fairing
Diameter: 5.2m
Height: 13m
Stages
2
SE
SW
Launching
South
531st
Mission
113th
Mission of 2025
557th
Mission
117th
Mission of 2025
208th
Orbital launch attempt