Another topic about pitot needed or not

[quote=“iskess, post:19, topic:18341, full:true”]
My experience is that an analog airspeed sensor is more reliable, but a digital is more accurate.[/quote]
In my experience this can not be generalized:

I had no I2C issues, but disturbances on the analog line. I2c and analog line issues depend both on cable routing, cable length, shielding and electromagnetical interference. If several sensors are connected to the i2c, the voltage of the inputs / outputs must be the same or you must have an active i2c-hub. The disturbing factors therefore depend on the individual frame structure.

If you have no i2c errors, analog is more noisy then digital and 4525DO is more noisy then newer ms5525:
New Airspeed sensor (MS5525) for ArduPlane 3.8

The next source of error, which can seriously affect reliability, is sensitivity to sunlight while airspeed calibration on startup.The 4525Do is very sensitive(the pitot probe was covered):

If the battery is plugged in under other lighting conditions than in flight and the sun can shine brightly on the sensor, the measurement is completely useless, if airspeed calibration on startup is enabled.
On conventional planes I have therefore enabled ARSPD_SKIP_CAL.

At the tiltrotor VTOL we check before each flight ARSPD_OFFSET,
since in the case of incorrectly high values, a stall while forward transition could be the consequence.

The ARSPD_RATIO is, on the other hand, consistently stable.

Only my experiences with 2 analog and four digital sensors.

Regards Rolf

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