Airspeed Sensors
Last updated
Last updated
Airspeed sensors are highly recommended for fixed-wing and VTOL frames. They are so important because the autopilot does not have other means to detect stall. For fixed-wing flight it is the airspeed that guarantees lift not ground speed!
Recommended digital airspeed sensors include:
All the above sensors are connected via the I2C bus/port.
-1: Disabled (no airspeed information used).
0: Synthetic airspeed estimation (groundspeed minus windspeed)
1: First airspeed sensor started (default)
2: Second airspeed sensor started
3: Third airspeed sensor started
The specific configuration for sensors that do not have a separate page is listed below:
Based on
MEAS Spec series (e.g. , )
(mRo store)
(Drotek).
(eagletreesystems)
Based on
Venturi effect airspeed sensor.
:::note Additionally, the can be connected to the CAN bus to determine not only high-accuracy airspeed, but also true static pressure and air temperature via onboard barometer and an OAT probe. :::
Airspeed sensor drivers are not started automatically. Enable each type using its :
Sensirion SDP3X:
TE MS4525:
TE MS5525:
Eagle Tree airspeed sensor:
You should also check is 1 (see next section - this is the default).
If you have multiple airspeed sensors then you can select which sensor is preferred as the primary source using , where 1, 2 and 3 reflect the order in which the airspeed sensors were started:
The airspeed selector validates the indicated sensor first and only falls back to other sensors if the indicated sensor fails airspeed checks ( is used to configure the checks).
The selected sensor is then used to supply data to the estimator (EKF2). The EKF fuses the airspeed data if it's above and has a low innovation compared to groundspeed minus windspeed.
Other than enabling the sensor, sensor-specific configuration is often not required. If it is needed, it should be covered in the appropriate sensor page (for example ).
Sensirion SDP3X: (provides overview of required settings), , .
Airspeed sensors should be calibrated by following the instructions: .
(source code)
