DJI Go 4 indicates wrong top altitude

[Jetmaker]

I have made 6 flights with max. altitudes of 253 ft, 220 ft, 79 ft, 174 ft, 151 ft, and 7 ft. The DJI Go 4 app shows top altitude of -97.9 ft. Not sure what is causing this?

 

[Meta4]

I have made 6 flights with max. altitudes of 253 ft, 220 ft, 79 ft, 174 ft, 151 ft, and 7 ft. The DJI Go 4 app shown top altitude of -97.9 ft. Not sure what is causing this?

I'm going to guess that you are flying from somewhere close to sea level?
The Top Altitude show in front of your flight records is not the highest you have flown above launch point.
For a reason known only to DJI, it shows the highest altitude you have flown from.
To complicate this, the altitude is derived from GPS which is not very accurate for altitude as this drone photo demonstrates:

 

[Jetmaker]

Yes, I was flying very close to sea level. Thank-you very much for your detailed answer!

 

[Meta4]

Yes, I was flying very close to sea level. Thank-you very much for your detailed answer!

Take a drive uphill and make a low level flight and see what that does to your displayed Top Altitude.

 

[DanMan32]

Here in FL, there isn't too much height to deal with so AGL or MSL, should be reasonably close. Those Go stats are a joke.
The individual flight stats used to be OK, but the all time was always wrong, even with my P3.

 

[Meta4]

Here in FL, there isn't too much height to deal with so AGL or MSL, should be reasonably close. .

The earth is not a perfect sphere. In some parts of the world, GPS will give you altitude errors like my example in post #2.

 

[DanMan32]

You're reading that from your photo I presume. I believe the OP is referring to the leader board in the app. It should be reading the altitudes from the txt logs.

 

[Meta4]

I believe the OP is referring to the leader board in the app. It should be reading the altitudes from the txt logs.

I do too. Which is why I said ... The Top Altitude shown in front of your flight records is not the highest you have flown above launch point.

 

[DanMan32]

I'm not too sure about that. According to Go, I've never been above 84ft with my P3. I have flown near 400ft with it lots of times.
My pre-refresh M2Z, supposedly 19ft. Post refresh, 129ft.

 

[Meta4]

I'm not too sure about that. According to Go, I've never been above 84ft with my P3. I have flown near 400ft with it lots of times.
My pre-refresh M2Z, supposedly 19ft. Post refresh, 129ft.

What's the altitude of the highest launch spot you've flown from? - not how high you've flown.

 

[Bengt]

I wish I had found this post earlier. I have been in touch with DJI support for a while, and today I got this answer:

"The "Top Altitude" refers to the Maximum take-off altitude, the maximum take-off height above sea level that has recorded among the flight."

It seems like a rather pointless statistic if you ask me, but hey, who am I to judge?

 

[Photo Hunter]

And so my top altitude (max take off) displays as nearly 200 feet below MSL! Flew this morning from a spot + 20 MSL. Any ideas why the difference?

 

[Meta4]

And so my top altitude (max take off) displays as nearly 200 feet below MSL! Flew this morning from a spot + 20 MSL. Any ideas why the difference?

Yes ... read earlier posts in this thread

 

[Photo Hunter]

Yes ... read earlier posts in this thread

Yep, did that already, including your previous comment:

"The Top Altitude show in front of your flight records is not the highest you have flown above launch point.
For a reason known only to DJI, it shows the highest altitude you have flown from."

My top altitude clearly does not show the highest altitude I have flown from unless -193 feet is somehow higher than +20 feet. Must be common core math.

 

[Meta4]

Yep, did that already, including your previous comment:

The explanation is in post #2 + post #6
Or the height is derived from barometer data and extrapolated assuming standard atmospheric pressure which can create similar errors.