SDA Tranche 1 Transport Layer A

Slip history

Tracking since Sat 10 Oct 2026, 10:32 UTC. 1 recorded change.

1. Sat 10 Oct 2026, 15:12 UTCRecorded change

   Status changed from In Flight to Success

2. Sat 10 Oct 2026, 15:07 UTCLL2 update

   Launch success.

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3. Sat 10 Oct 2026, 07:40 UTCLL2 update

   Liftoff!

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4. Sat 10 Oct 2026, 07:23 UTCLL2 update

   Unofficial Re-stream by SPACE AFFAIRS has started

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5. Sat 10 Oct 2026, 00:45 UTCLL2 update

   Tweaked T-0.

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6. Fri 9 Oct 2026, 14:57 UTCLL2 update

   Tweaked T-0.

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7. Thu 8 Oct 2026, 00:12 UTCLL2 update

   Delayed to NET October 10.

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8. Wed 7 Oct 2026, 20:35 UTCLL2 update

   Delayed to NET October 9.

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Mission

SDA Tranche 1 Transport Layer A on Falcon 9 Block 5 from Space Launch Complex 4E. Launch time, status and recorded date changes from Launch Library 2.

Tranche 1 Transport Layer A 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 Northrop Grumman.

Mission type

Government/Top Secret

Orbit

Polar Orbit

Launch timeline

Times are relative to liftoff.

1. T-38 minSat 10 Oct, 09:01 CEST

   GO for Prop Load

   Launch director verifies go for propellant load

2. T-35 minSat 10 Oct, 09:04 CEST

   Stage 1 LOX Load

   Start of liquid oxygen loading in the first stage

3. T-35 minSat 10 Oct, 09:04 CEST

   Prop Load

   Start of propelland loading

4. T-16 minSat 10 Oct, 09:23 CEST

   Stage 2 LOX Load

   Start of liquid oxygen loading in the second stage

5. T-7 minSat 10 Oct, 09:32 CEST

   Engine Chill

   Start of engine chilling

6. T-1 minSat 10 Oct, 09:38 CEST

   Tank Press

   Fuel tanks are pressurized to flight levels

7. T-1 minSat 10 Oct, 09:38 CEST

   Startup

   The onboard computer takes control over the countdown and runs last checks

8. T-45 sSat 10 Oct, 09:38 CEST

   GO for Launch

   Launch director verifies go for launch

9. T-3 sSat 10 Oct, 09:39 CEST

   Ignition

   Start of the engine ignition sequence

10. T-0Sat 10 Oct, 09:39 CEST

    Liftoff

    First upwards movement of the rocket

11. T+1 min 4 sSat 10 Oct, 09:40 CEST

    Max-Q

    Maximum dynamic pressure

12. T+2 min 14 sSat 10 Oct, 09:41 CEST

    MECO

    Cut-off of the main engine

13. T+2 min 18 sSat 10 Oct, 09:42 CEST

    Stage 2 Separation

    Separation of the second stage from the first

14. T+2 min 25 sSat 10 Oct, 09:42 CEST

    SES-1

    First start of the second engine

15. T+2 min 31 sSat 10 Oct, 09:42 CEST

    Booster Boostback Burn Startup

    Start of the booster boostback burn

16. T+3 min 4 sSat 10 Oct, 09:42 CEST

    Fairing Separation

    Separation of the payload fairing

17. T+3 min 24 sSat 10 Oct, 09:43 CEST

    Booster Boostback Burn Shutdown

    End of the booster boostback burn

18. T+6 min 9 sSat 10 Oct, 09:45 CEST

    Entry Burn Startup

    Start of the atmospheric entry burn

19. T+6 min 21 sSat 10 Oct, 09:46 CEST

    Entry Burn Shutdown

    End of the atmospheric entry burn

20. T+7 min 15 sSat 10 Oct, 09:46 CEST

    Stage 1 Landing Burn

    Start of the first stage landing burn

21. T+7 min 19 sSat 10 Oct, 09:47 CEST

    Stage 1 Landing

    Landing of the first stage

Launch pad

Space Launch Complex 4E

Vandenberg SFB, CA, USA (US)

Coordinates: 34.632, -120.611