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Preflight sensor calibration

Could be implemented a preflight sensor (e.g. analog airspeed sensor) calibration, triggered through an RC switch ?
This way we could eliminate the need to connect the FC to MP or QGC before every flight.
Thanks, Norbert

Why not power cycle before takeoff ?

Because, when I power it up, never shows close to 0 air speed.
So I have to calibrate, then take off.
To calibrate, I have to connect the fc to qgc, fisicaly, through USB.
I’d like to avoid this, if possible.

Then you do something wrong during powerup. During powerup AP runs the same airspeed sensor calibration routine that runs when doing preflight calibration (btw, we usually do preflight reboot instead of calibration). Do you cover your pitot tube during powerup ?

Yes, I do cover it up. It’s a Matek analog one, I did also a ratio calibration flight, but every time I power the system, I got 5-6-7 kmh airspeed. After calibration, it settled down to near 0.

Hello Norbert,
I also have the experience that airspeed sensors have different and better calibration values a few minutes after booting than immediately when power is applied in “cold” state. 7 km/h at standstill seems like a lot at first. But the dynamic pressure is only proportional to the second root of the speed. So 7 km/h too high displayed speed at 0 km/h means only a little less than 1 km/h at 40 km/h .
The difference is only critical in slow transitonspeed Tiltrotor . VTOLS below 10 m/s. For this I take the SDP33, which does not need zero calibration.

Rolf

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Mine is mounted on a mini Crosswind plane.
So, no slow speed involved.
During flight, the airspeed sensor is pretty accurate.

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