VTOL without airspeed sensor

Hi, I am trying to fly my VTOL without airspeed sensor.
I found that I should change SYS_HAS_NUM_ASPD to 0

but I couldn’t find such parameter in QGC parameter setting

I checked that the firmware is the latest version (1.14.0)
What should I do?

i wll thanks a lot if you help me.

CBRK_AIRSPD_CHK change this parameter to 162128. this will disable the precheck of airspeed sensor.

@JiwonChoi Do you have the airspeed sensor installed and want to disable it, or you don’t have the sensor at all? I’m building a VTOL which doesn’t have that sensor and in QGC I also don’t see the parameter, so my guess is that if no sensor is attached the airspeed module is not even called, but not completely sure about that

My answer was not correct, sorry for that but I did not know that things changed and I was also in your same situation
Parameters are changed since June of last year. CBRK_AIRSPD_CHK and FW_ARSP_MODE are now called SYS_HAS_NUM_ASPD and FW_USE_AIRSPD (logic is a little bit different, but the idea is the same)
So if the version you are using is not up to date with the main branch of PX4 (I have no idea on which is the default version currently running on QGC) you should set CBRK_AIRSPD_CHK = 162128 as @Dhruvil correctly said. Since this just disables the check for the sensor, but does not change the internal logic of the controller, it would just assume that no measures are available and will use FW_AIRSPD_TRIM (assuming that is the actual TAS) where needed . So you need also to set FW_ARSP_MODE = 0
I would also set ASPD_PRIMARY = -1 , but probably is not needed
Hope that this will help you

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Its not true, even if airspeed sensor is not attached, you will get pre-flight error, invalid airspeed sensor or calibration of sensor is required.

Yes those parameters changed between 1.14 and main.

@JiwonChoi if you’re using 1.14 then you have to select that in the “Version”