Altitude accuracy

[bill1950]

Does anyone have any info on the accuracy of the altitude read out on the Mini 2. I few times I have noticed that when I was hovering right after take off and it read at 5 ft when it was half that distance. I have also checked it by flying it to six feet, my height and it was actually around 8 feet. Is there a plus or minus on the altitude and is there a way to calibrate or recalibrate it? I don’t fly where altitude is critical but would like to know in case I run into an area where it would be, flying over trees, RTH etc. etc.

 

[netfolks2000]

I've also noticed a variation. It'll say 50 ft which I consider safe for RTH but when it arrives it looks more like 80ft.

 

[Phantomrain.org]

There is no way to calibrate it, other than the IMU however you can test it before you take off and use the 3 Ft marking on auto take off.

Mark what ever you might be off and add or subtract as you fly , but some fluctuation is normal.

Phantomrain.org
Gear to fly in the Rain ..

 

[Deleted member 103366]

you might find MAVIC 2 ENTERPRISE ALTITUDE ISSUES interesting

 

[bill1950]

Will do, going out to fly in a few and I will measure it. I know if it is off a foot or two not going to make much difference in RTH or flying over things. Was more curious if it was normal. I had a mavic air and it was pretty much dead on. Thanks for the help

 

[bill1950]

you might find MAVIC 2 ENTERPRISE ALTITUDE ISSUES interesting

Thanks for the sending the post, very inter! Scary that it could be 20 or thirty feet off. I will probably set my RTH accordingly.

 

[Deleted member 103366]

I have seen 10m recommended as suitable clearance.

 

[Meta4]

Does anyone have any info on the accuracy of the altitude read out on the Mini 2. I few times I have noticed that when I was hovering right after take off and it read at 5 ft when it was half that distance. I have also checked it by flying it to six feet, my height and it was actually around 8 feet. Is there a plus or minus on the altitude and is there a way to calibrate or recalibrate it? I don’t fly where altitude is critical but would like to know in case I run into an area where it would be, flying over trees, RTH etc. etc.

The altitude data comes from a barometric sensor.
It's common for the altitude accuracy to drift 10 ft or more over the duration of a flight.

 

[Dave Maine]

My Mavic Air varies a lot. Sometimes it is within a couple of feet, others off 10+ feet. True as well for P4adv, and P34K.

 

[AVLJMA]

I've also noticed a variation. It'll say 50 ft which I consider safe for RTH but when it arrives it looks more like 80ft.

Yesterday I went up to 300 ft, did an oval and then came back down to check the new props. The Mini 2 was at about 10 feet off the ground and the RC showed -10 feet. I have never seen a negative digital display before. I have over 500 hours flight time between the Mini 2 and the MA2 and have never seen that before. I can't explain that.

 

[wardtom084]

I would guess very inaccurate. Sonar, radar if you want real figures. I know I go up to 400 feet at home and go down the creek about a mile away and it cannot still be 400 feet. Do this if you want to really experiment. Cut some twine etc to 100 or 200 feet. Take it up to 400 feet, do some flying and bring it back home. Would bet the figures are way off.

 

[Meta4]

I have never seen a negative digital display before. I have over 500 hours flight time between the Mini 2 and the MA2 and have never seen that before. I can't explain that.

As mentioned in post #8 above, it's common and normal for the indicated altitude at the end of a flight to be wrong.

To see a negative altitude number, all you have to do is fly down from a high point.

 

[wardtom084]

 

[wardtom084]

Can't seem to edit above and keep the pix. Take off altitude 2,142.3 and land -7.5

 

[Meta4]

Can't seem to edit above and keep the pix. Take off altitude 2,142.3 and land -7.5

The first number is absolute altitude (height above sea level)
The 2nd is relative height - relative to launch point +/- a little for sensor drift or air pressure change during the flight.

 

[BigAl07]

Yesterday I went up to 300 ft, did an oval and then came back down to check the new props. The Mini 2 was at about 10 feet off the ground and the RC showed -10 feet. I have never seen a negative digital display before. I have over 500 hours flight time between the Mini 2 and the MA2 and have never seen that before. I can't explain that.

Most likely it's rare because we don't normally pay attention to "Landing Height" since its irrelevant because the UAS is safely on the ground. I'd bet if you go back and look at past data you'd see several instances of "Sensor Drift" indicating a negative figure at landing.