Unhealthy airspeed sensor disable using

How is the Ardupilot going to deal with the unhealthy airspeed sensor? I have one airspeed sensor (enabled).

What do I need to have a redundancy for the airspeed sensor (totally blocked or partially blocked)? For example, to switch from an unhealthy airspeed sensor to the estimated wind speed algorithm I noticed that the 4 parameters (AHRS_WIND_MAX, ARSPD_WIND_MAX, ARSPD_WIND_GATE, ARSPD_OPTIONS) are somehow related to this problem. Please advise me to get the best setup, such as good redundancy.

https://ardupilot.org/plane/docs/fixed-wing-faq.html#what-happens-if-an-airspeed-sensor-fails-in-flight

Ardupilot doesn’t have means of detecting fail active airspeed sensor though if you have two then if the active EKF was using it you should see lane switch as long as the other lane has good enough estimate. Though it is not guaranteed.

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When using 4.4.x firmware, when you install two airspeed counters, it will switch lanes when it detects a loss of airspeed while flying. I have verified it many times, it can only reduce the possibility of crashes, but it is not 100% effective.

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it can only reduce the possibility of crashes, but it is not 100% effective

regarding to the AHRS_WIND_MAX, with the airspeed clipping mechanism in place:

  • The system will compare the reported airspeed (250 knots) to the GPS ground speed (150 knots).
  • Because the difference (100 knots) exceeds the AHRS_WIND_MAX limit of 20 knots, the system will “clip” or adjust the reported airspeed value.
  • The clipped airspeed value will be constrained to within 20 knots of the ground speed, so it would be adjusted to either 170 knots or 130 knots, depending on the assumed wind direction (headwind or tailwind, respectively).
    does this example illustrate the AHRS_WIND_MAX correctly?