Mission Planner displays TFMini rangefinder distance in feet (maybe), not meters

I’m using MP 1.3.56 and ArduPlane 3.8.5 with an mRo Pixracer. As you can see from the log excerpt during landing, the green sonr distances track the red baro altitudes pretty well. Also note that the rangefinder is limited to about 6 meters.

In Mission Planner’s “Quick” view, the Sonar Range displays feet (I think) instead of meters.


Do you think that the auto-landing logic uses the meters as recorded in the log, or the value as displayed by Mission Planner?



I am having the same issue. Did you ever find a solution?

So in your example your sonar is actually 12.04 feet, but it displays 12.04m. So presumably the EKF2 uses 12.04/3.3 m for control?

Hi Jack,

I looked in my notes and found no resolution. I used the TFMini rangefinder with good success though, and always configured it in units of either centimeters or meters. The auto-landing flight tests were successful so I reckoned that the system was also using centimeters and meters.

I think I just removed the rangefinder part from the Mission Planner display. The altitude display in feet was accurate so it must have been translation from meters by the Mission Planner software.

Good luck,


OK thanks. Actually I am using the TFMini Plus for I2C now.