ALTIMETER CALIBRATION ERROR

[E90RAW]

I have noticed my M2P and M2Z both will have inaccurate heights noted on the SC. This seems to be a frequent occurrence to the point that I fly them back home and land on terra firma to reset the unit before flying again. I have had one crash so far when I thought I was far enough above the tree line based on the altimeter. Any thoughts other than just keep landing to reset periodically and being aware?

 

[sar104]

I have noticed my M2P and M2Z both will have inaccurate heights noted on the SC. This seems to be a frequent occurrence to the point that I fly them back home and land on terra firma to reset the unit before flying again. I have had one crash so far when I thought I was far enough above the tree line based on the altimeter. Any thoughts other than just keep landing to reset periodically and being aware?

How large is the error?

 

[E90RAW]

How large is the error?

Its not large, maybe 3-5 feet. Sometimes it will show (-) negative number, but no more than 3-5. It resets no problem once I hit the ground..

 

[sar104]

Its not large, maybe 3-5 feet. Sometimes it will show (-) negative number, but no more than 3-5. It resets no problem once I hit the ground..

The altimeter resets automatically on landing and on motor start. That kind of discrepancy is entirely normal for barometric height measurements.

 

[E90RAW]

The altimeter resets automatically on landing and on motor start. That kind of discrepancy is entirely normal for barometric height measurements.

got it, thanks!

 

[new2mavic]

The atmospheric pressure changes over time. After a 25 minute flight, my M2P has once indicated that the altitude of the takeoff/landing point has changed by 3 meters.

 

[gnirtS]

Fairly sure the altimeters arent temperature compensated. I get a landing discrepancy every single flight from takeoff and landing (same on M1).. Usually in the region of 5-8ft, worst ive seen is 20. *ALWAYS negative*
Not that its an issue anyway, VPS is used to keep it off the ground if its low anyway.

 

[Delmarksman]

I have been having this issue as well, This is my second M2P and both had the issue. My new M2P was just received from DJI last week, first few flights I noticed anywhere from a few feet to 35' off from the take off point. It's never less than 5-6' even on short flights, any distance away from the home point.

I rarely use the RTH, but should I ever need to, or there were an auto RTH for some reason, this does concern me.

 

[E90RAW]

I have been having this issue as well, This is my second M2P and both had the issue. My new M2P was just received from DJI last week, first few flights I noticed anywhere from a few feet to 35' off from the take off point. It's never less than 5-6' even on short flights, any distance away from the home point.

I rarely use the RTH, but should I ever need to, or there were an auto RTH for some reason, this does concern me.

Since my original post above I have also noticed the negative numbers ranging from 5 to 15 feet. I always make sure I round up 20 feet above any object I want to avoid just in case. This weekend I flew over water/ocean and wanted to stay 10 feet above to counter wind but instead kept it at 30 feet. Just one of those things to be aware of I guess.

 

[bburnett15]

I have this as well. Doing some repetitive exercises to hone my skills, one spot originally noted as 21+ ft kept lowering every time i went by that spot to the point where it was reading 4.7 ft and it was at the same height (visually) as when it registered 21+ ft.

 

[Meta4]

I have this as well. Doing some repetitive exercises to hone my skills, one spot originally noted as 21+ ft kept lowering every time i went by that spot to the point where it was reading 4.7 ft and it was at the same height (visually) as when it registered 21+ ft.

That's common and completely normal.
That's just the nature of using a barometric sensor for altitude measurement.
It isn't a problem for flying your drone.