Altitude reading way off

[BudWalker]

Look, I can understand a little skepticism. It wasn't a perfect test. So, I went out today to test again...

After a little flying, it was almost 10ft off. Granted, I was 8ft away from my Home Point

A little closer to the home point and its getting worse.

I can't get much closer and it's almost 13ft off.

And keeps getting worse...

By the time the battery was drained, it was almost 20ft off

I realize that this may not seem like a bit deal to some since you can still use your VPS but VPS has it's limitations and I've even had issues when flying over water so I may need to have it off.

You could measure the barometer error by looking at the baroAlt value in the .DAT file. Let the Mavic sit on the ground with the battery on for 10 minutes and then retrieve the .DAT file for that "flight". Then look at the beginning and end baroAlt values. You might want to do two tests, one with the Mavic upside down so it doesn't get as hot.

 

[colonel00]

Interesting idea. I guess my bigger question is still about what is causing the error. As most people aren't seeing this issue, I have to wonder if it's because I'm flying from an elevated position and often dropping down below the home point since I'm up on a levy. Still though, the progression of the deviation can't really be explained unless I do something like you suggest. I just don't know if leaving it grounded will replicate the issues.

 

[f3honda4me]

Very interesting, it does indeed seem to be something that shouldn't quite be. I would pass this along to DJI support personally.

 

[arcolog2]

Tomorrow I'll be flying from a mountain top here in Hawaii, so I can see if I have an issue like this due to the flying down thoughts.
How about when you have this issue, land it, take off again with new home position setting and it should reset the altitude, maybe it will read jacked up or maybe back to normal? Doesn't tell me anything but info you can pass to DJI

Sent from my SM-N910V using Tapatalk

 

[arcolog2]

Ok, I flew on battery but forgot to see what altitude it said when I came back to home. I do however wonder why no matter where I take off from it says home point set at 164ft"? No matter if I am at sea level on the beach or 1000ft up a mountain

Sent from my SM-N910V using Tapatalk

 

[IADRN43]

Would the mavic barometric pressure register a change as the mavic warms up during flight? Moving would wick away the heat, right? Would hovering produce enough of a "cocoon" of temperature to fool the sensors to read funny?

 

[Andrew F]

Look, I can understand a little skepticism. It wasn't a perfect test. So, I went out today to test again...

After a little flying, it was almost 10ft off. Granted, I was 8ft away from my Home Point

A little closer to the home point and its getting worse.

I can't get much closer and it's almost 13ft off.

And keeps getting worse...

By the time the battery was drained, it was almost 20ft off

I realize that this may not seem like a bit deal to some since you can still use your VPS but VPS has it's limitations and I've even had issues when flying over water so I may need to have it off.

Mine does the same thing. I fly high except when in VLOS to be sure there are no unplanned ground impacts.

 

[Logger]

Ok, I flew on battery but forgot to see what altitude it said when I came back to home. I do however wonder why no matter where I take off from it says home point set at 164ft"? No matter if I am at sea level on the beach or 1000ft up a mountain

Sent from my SM-N910V using Tapatalk

I suspect when you take off it is telling you "RTH is set at 164 feet" as you have it set to 50m. This altitude is relative to your take off point not sea level.

 

[arcolog2]

I suspect when you take off it is telling you "RTH is set at 164 feet" as you have it set to 50m. This altitude is relative to your take off point not sea level.

Ohhh I like it. Thanks man. I'll change it and see if that changes, English translation problems from DJI lol

Sent from my SM-N910V using Tapatalk

 

[OkobojiDrone]

My Mavic altitude is ALWAYS incorrect. Which is frustrating because my phantom 3 was great at it.

My altitude will read 20'-50' above ground when it touches down back at the home point. Every time.

I think what happens is it loses actual altitude every time I move around from spot to spot. I can see it happen. But then it doesn't translate that onto the screen.

So when it sags 2-4' at every position change no wonder it reads higher at the end of the flight. Just don't understand why 1) it sags, and 2) why it doesn't change on the screen.


Sent from my iPhone using MavicPilots

 

[Disloyal Customer]

I just flew a short Mavic 2 Enterprise Dual mission to check out a neighbor's cabin about a mile away to see if the snow had melted off his roof. I'm up on an elevated spot and his cabin is about 300 feet below mine and the ground slopes down to his place so when I fly the mission I can maintain line of sight the whole time. Did this with Litchi. I take off at 100' (above the launch point where I am) and when it gets to his house it's obviously higher than that.

When the drone came back, it was showing 100' on the screen, but it was WAY up there for some reason. When it landed it showed -300 feet as the altitude.

I'm not sure if this is related, but seems it could be.