Air speed is less than ground speed

ArduPlane
,
1

Good day.
Today I had a strange situation, the entire flight the air speed was 10-20 km/h less than the ground speed. There was practically no wind. Before the flight I calibrated the airspeed sensor when it was closed. BEFORE takeoff, it showed ground speed of 0, air speed was 1-3 km/h. Immediately after take-off, the ground speed became greater than the air speed, regardless of the direction of the aircraft. As soon as the plane landed, the airspeed became faster than the ground speed again. What could be the problem?
Explanation of the screenshots:
The first - before take-off, the second - immediately after take-off, the third - in flight, the fourth - immediately after landing.

Screenshot_1
Screenshot_11320×1022 148 KB

Screenshot_2
Screenshot_21338×1031 157 KB

Screenshot_3
Screenshot_31333×1001 167 KB

Screenshot_4
Screenshot_41335×1005 147 KB

Log file (.BIN)^

2

Hi Michal,

without a logfile of the flight (*.bin) one can only make speculations. The best thing to do is to post a link to the logfile.

Rolf

3

Added a link to the log file.

4

The airspeed sensor behaves completely intact.

Screenshot 2023-02-18 211837
Screenshot 2023-02-18 2118371565×778 87.4 KB

But you should calibrate ARSPD_RATIO correctly ( Calibrating an Airspeed Sensor — Plane documentation ).
According to the circles you flew at the beginning, you can also manually change ARSPD_RATIO to 2.67.

Rolf

5

Thank you. I will check on the next flight. it seems to me that I calibrated, although it may not be so. Thank you again.