Communications
SDA Tranche 1 Transport Layer
The Tranche 1 Transport Layer is a mesh network of 126 optically interconnected satellites in near-polar low Earth orbit planes, intended as a resilient, low-latency data backbone for the Proliferated Warfighter Space Architecture. SDA reported 21 Transport Layer satellites on its third Tranche 1 launch.
- Operator
- Space Development Agency (U.S. Space Force)
- Launch vehicle
- Falcon 9
- Launch site
- Space Launch Complex 4 East, Vandenberg Space Force Base, California
- Target orbit
- Low Earth orbit, 750 to 1,200 km altitude (Transport Layer, all tranches)
- Altitude
- 750 to 1,200 km (Transport Layer); about 1,000 km on the third Tranche 1 launch
- Schedule
- SDA does not publish upcoming launch dates. The date on the calendar comes from the public launch schedule at Spaceflight Now and can change.
Instruments and payloads
- Optical communication terminals (at least four simultaneous links)
- Link 16
- Ka-band RF
- BMC3 module for onboard data processing, storage and fusion
Primary source: sda.mil. Facts checked on 2026-10-10. Dates are the operator's targets and can change; this page does not report launch outcomes.