Airbus Defence and Space


Astrix 120 fiber optic gyro

The Fiber Optic Gyro (FOG) is a fully static inertial measurement technology that is free of any moving part and have a much better reliability than classical mechanical gyroscope technologies.

Astrix 120 is made of 4 independent closed loop FOG 120 gyroscope channels, assembled on a common baseplate.

This configuration offers a redundancy and a failure detection capability. It improves also the nominal performances, by using 4 channels ON at the beginning of the mission (then 3 channels ON after one failure).

Features / technical details

Main features

  • Mass 7,5 kg
  • Volume 410 x 260 x h170 mm
  • Power 6 W (max) per ON channel


  • Bias stability 0,01°/h
  • Angular random walk : 0,002°/ square-root(h)
  • Scale factor 100 ppm


  • 4 independent angular rate detection axes in a skewed configuration
  • high inertial performances
  • 5 year continuous operation
  • 15 year continuous operation for telecom version
  • 1553B digital interface
  • electrical stimulation capability for internal testability and SCAO ground test.


  • 1553 data bus interface (one per channel)
  • RS 422 stimuli and data interface
  • external synchronisation link interface for high accuracy time tagging
  • 21-51V power bus (99-101 V for telecom option)


  • Thermal : -10 to +50 °C; -30 to +70 °C (telecom option)
  • Vibrations: 18.2 g RMS, 20g sine
  • Shocks : 800g SRS 2000Hz/10kHz



Astrix 120 FOG can satisfy the needs of most Earth Observation & Telecom satellites.

Reference customers