Airspeed problem

I am using plane3.8.5, after calibrating the sensor, I have used the MS4525 airspeed sensor. I have not taken off yet. I found that the airspeed value displayed on the ground station always changes drastically. As shown in the figure, this is normal. ? thank you very much
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From my own observations, 0-2m/s noise is normal for the MS4525, 3m/s is worrying but still flyable. That said, some things you may want to try that helps reduce the noise:

  • Make sure the sensor is stably mounted; the sensor is very sensitive to external disturbances. If it is allowed to vibrate together with the moving air, the noise will naturally be higher
  • Set ARSPD_TUBE_ORDER to 0 to prevent false positive readings in the event that the static port is receiving excessive pressure.

I did some work on measuring airspeed sensor noise previously, which you can find here: MS5525 vs MS4525 airspeed sensor noise

Thank you, I also saw that the official website said that the airspeed jump at normal time is normal, but I see the method of calculating the airspeed in the code, why not use the atmospheric density?