A catastrophic thruster control unit failure caused Intelsat’s Galaxy 37 satellite to become inoperable in April 2025, leaving over 200 broadcast and telecommunications customers without service across North America. The failure resulted in approximately $180 million in estimated losses and forced emergency service migrations to alternative satellites.

The Federal Communications Commission investigation, completed in August 2025, determined that a redundant propulsion system controller experienced a firmware corruption event that cascaded through both primary and backup thruster systems. Intelsat initially detected anomalous telemetry on April 12, 2025, but the satellite became unrecoverable within 72 hours as attitude control degraded beyond operational parameters.

What Caused the Galaxy 37 Satellite Failure?

The root cause was traced to a software vulnerability in the thruster control unit’s command processing module, manufactured by Orbital ATK. The firmware failed to properly isolate a corrupted memory sector, allowing erroneous commands to propagate to the propulsion valves. This resulted in uncontrolled fuel venting and complete loss of three-axis stabilization. The satellite, launched in 2008 with a 15-year design life, was operating within its expected lifespan when the failure occurred at the C-band and Ku-band frequencies serving critical infrastructure.

How Will Intelsat Replace Galaxy 37 Services?

Intelsat transferred affected customers to Galaxy 3C and Horizons 3e within 30 days of the failure. The company expedited the launch of Galaxy 37 replacement (Galaxy 42) to Q4 2026, providing service credits totaling $45 million to affected customers during the transition period.