How can I switch off the yaw damper in an Airbus A350? In the A320, this can be done by switching off the FAC, but the A350 doesn't have a FAC switch; it has prim and sec instead of FAC and ELAC.

  • 2
    $\begingroup$ I'm curious why you are asking. Would you mind sharing your interest in the A350, and why you would want to know something so specific? $\endgroup$ Jan 17, 2019 at 0:43
  • 3
    $\begingroup$ I'm an engineer at a flight simulator company and I've just been put on the A350 project but I'm not familiar with the cockpit layout. $\endgroup$ Jan 17, 2019 at 13:06
  • $\begingroup$ As a simulator engineer, shouldn’t you somehow be able to receive documents from aircraft OEM detailing the systems to be simulated? $\endgroup$ May 26, 2019 at 11:26
  • $\begingroup$ If you want to buy a simulator you pay for the data package but it is the simulator manufacturer who will get it $\endgroup$
    – user40476
    May 26, 2019 at 11:38
  • $\begingroup$ @MichaelHall This is a Q&A site that frequently receives specific questions about an aircraft's feature or behavior. You don't need to play security and find out why folks are asking a specific question. $\endgroup$
    – zymhan
    May 26, 2019 at 13:11

2 Answers 2


On the simulator normally you can simulate the failure of the yaw damper actuators which has the same effect as switching off the yaw damper. On the aircraft you can’t do it from the cockpit panels without switching off lot of other functions

  • 2
    $\begingroup$ The thing is there are no yaw damper actuators on new A330s, A345 and above. They have all-FBW rudders. $\endgroup$
    – user71659
    May 25, 2019 at 20:34
  • $\begingroup$ As far as I remember on Airbus in addition to the ADIRUs you have lateral specific accelerometers to the FBW; you have to switch off all these by means of push buttons and breakers, but this is not enough because in Airbus you have an emergency autonomous yaw damper unit that uses hydraulic power to generate electrical power to provide yaw damper. $\endgroup$
    – user40476
    May 26, 2019 at 9:06

If you prevent the yaw damper function to be calculated it will switch off. As yaw damper is calculated using lateral data from ADIRUs and specific FBW lateral accelerometers you need to switch off all these; the ADIRUs by push buttons and the lateral accelerometers by specific breakers. On some Airbus you still have an emergency AUTONOMOUS yaw damper unit, some models are fully electrical and use up to the battery power, so you pull the relevant breaker, but some models use the hydraulic power to generate their own electricity so you need to switch off the corresponding hydraulics, leaving active the only hydraulic that the autonomous yaw damper does not use. On the other hand note in direct FBW mode the yaw damper is degraded but still functional, so being in direct mode is not sufficient to inhibit the yaw damper. But by putting off the yaw damper most probably you will be in direct law.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .