Can be GY-US42 ultrasonic range finder usefull for plane landing?

I want to add some affordable range finder to my Mini Talon plane to assist autolanding.

I real life tested responses of GY-US42 on my Mini Talon and results were much worse, than values stated in the sonar specification.
Over the grassland it gave me usefull responses at best between 0,4-1,8 m, but anyway the measurements consisted many errorous readings of either 0m or 7,2m (theoretical max. range).
To have some idea see this graph:

Red and green lines are altitude from two baros, blue is rangefinder response.

Before I crash my plane during an autolanding attempt, can someone tell me if such responses have any chance to be usefull?
Will be error readings of 0 and 7,2m filtered if I define rangefinder correct reading range 0,4-1,8m?

To have some idea how this part of flight shown in the graph looked like see this video.

I tested also TOF400C VL53L1 infrared range finder and for outdoor it was completely useless. At daylight it gave only some 10-20cm range, too little for the plane.

Any other idea for a range finder under $30 providing usefull readings for a plane?

You could try the TF luna lidar. It’s cheap and on copter I had useful readings up to 8 meters. To be positioned far from the GPS because it emits EMI disturbances.

Thanks! Can you please share more details about your tests? Was it outside on the direct sunlight and over the grass?
Any details wellcome!

Try here:

Bought Benewake Luna and tested on the plane (mini Talon). Results are much better than GY-US42 ultrasonic. At full noon sunshine above grass or soil provides good results at 6+ meters at speed 60-70 km/h. Not tested automatic landing yet.

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