Hi, new P4 owner here.

I have encountered two different issues in my first two flights. My flight logs show negative altitudes. I have started flying from ground level and did not go lower from a hill or something like that. Just a little bit higher.
I have calibrated the IMU after cooling the aircraft on a level surface and I have calibrated the compass at the location I flew.

Also I got a class C or D (can't remember exactly) airspace error where I used to fly with a P3S without any warnings.

Can anybody shed some light on these?

Thanks in advance.

Do a recalibration of the drone imu compass etc

Hopefully that re-calibration works out for you.  What was the max height it recorder you at?  Were they all negative readings?  

Gotta watch out for those underground airports.  They just do not show up on the sectionals.

Mine often shows -50 feet on landing (Take-off zero), but yours at -200 feet is really odd.

When you play it back in Fight Review in GO, how does the displayed altitude behave?  Mine will seems okay, then it drops to maybe 6 feet, then a while later jumps way back up, then down, and near the end of the flight it is really down.  This is mostly flat field flying over a distance of 3,000 feet too.  I would think the thing with all its underbelly sensors would report zero upon landing, but it doesn't in my GO playbacks.

It might be the barometer is getting some turbulence within the aircraft's covers.  Maybe the bottom VPS sensing system is getting into the mix too, albeit wrongly.  It does seem different on still air days too verses windy days where it's worse.  Might be a combination of the barometer not being in static air inside the frame as well as the GO program or the firmware being off or sampling wrong.  The iPad Air 2 + Cellular I have barometer built into it is much more stable in readings than the one in the drone, ime.  Something is screwy in the drone someplace and one GO update was reported as addressing some of that too.

Fwiw, I was reading about Trimbal's surveying drone which claims an accuracy to within 7 inches.  No where have I seen that sort of accuracy with the P4 I have, it's more like 7 meters.

Good luck sorting it out.

fansa84fe8a4 Posted at 2016-12-24 12:51
Mine often shows -50 feet on landing (Take-off zero), but yours at -200 feet is really odd.

When you play it back in Fight Review in GO, how does the displayed altitude behave?  Mine will seems okay, then it drops to maybe 6 feet, then a while later jumps way back up, then down, and near the end of the flight it is really down.  This is mostly flat field flying over a distance of 3,000 feet too.  I would think the thing with all its underbelly sensors would report zero upon landing, but it doesn't in my GO playbacks.

How do I play it back? Could you explain, I couldn't find a way to play it back, thank you!
I couldn't get a screenshot but twice, the app told me that I have a P3P therefore I should use the DJI GO app instead of DJI GO 4.

Now it's showing that I own an Inspire. And 19 flights that I haven't involved.

Looks like you are using GO 4 rather than Go 3.x.  The mods here have said to use the GO 3.x version for the P4 even though it shows the P4 in the setup in GO 4.  Don't know what affect it has, but I'm guessing you are using GO 4 since the word TOP "ALTITUDE" is spelled correctly where in GO 3.1.1 iOS it is spelled incorrectly as MAX TAKEOFF "ALTTITUDE" with three T's in altitude (DJI, ahem!).

Anyway, in GO 3.1.1 I have on the iPad, there is a little triangle in the upper left on the main page.  Select that and it opens much like your page shows.  Under "FLIGHT LIST" on the right (Yours shows "FLIGHT DATA(DJI AIRCRAFT"), your recent flights should be shown.  Pick one and it opens a player and you can hit the playback arrow and see the flight in review and watch your altitude variations which are likely wrong if you were flying flat.

I play mine back often and scratch my head as to why the altitude wavers flying straight and level, and sometimes apparently it's flying underground.  No amount of IMU, VPS, compass cals address it.  I thought I had a bad spirit level at one point, but the negative altitudes soon came back later following yet another update.

Why yours shows nothing stored on the right might be GO4 too as there have been bugs in recording of flight logs/records recently with some updates.  Sometimes the recent's get erased, but the priors from months long ago remain.  These things have a lot of voodoo and black magic going on at times - and not for the good either.

Good luck.

There's nothing wrong with your Phantom and it needs no fixing.
There is a well known fault in the Top Altitude show in that part of the app.
Go and check the individual flight records and they should show correct altitudes.

Thank you for the clarification.

Do I really need to use DJI GO app instead of DJI GO 4? The new app was one of the reasons made me choose Phantom 4 and would be a huge bummer if I can't use it with the new app. Why do I see an inspire on my app with 20 flights?

Is this a short term thing or will phantom 4 be always used with DJI GO 3?

That's odd.

berkay Posted at 2016-12-25 00:06
Thank you for the clarification.

Do I really need to use DJI GO app instead of DJI GO 4? The new app was one of the reasons made me choose Phantom 4 and would be a huge bummer if I can't use it with the new app. Why do I see an inspire on my app with 20 flights?

Why do you not use DJI Go 4 ?

http://forum.dji.com/thread-75904-1-1.html

It is indeed odd. Even though my P4 hovers way more solid compared to the P3S I can't say the same on the software part.

I never owned an inspire. Why does it show up? Why DJI GO 4 app tells me that I have a P3P and need to connect to GO app instead of GO 4?

Thanks for the answers, I appreciate advises.

berkay Posted at 2016-12-25 08:40
It is indeed odd. Even though my P4 hovers way more solid compared to the P3S I can't say the same on the software part.

I never owned an inspire. Why does it show up? Why DJI GO 4 app tells me that I have a P3P and need to connect to GO app instead of GO 4?

My guess is it is showing the inspire because you do not have the app connected to the RC connected to the AC. Everything has to be on and connected to correctly report the aircraft (At least in the Go app 2/3.x).

Thank you Robert.


It's really windy out there so I have cancelled my flight but anyway I guess today forum will be flooded with all those Christmas gift problems and may not be the best day to get good answers.

I'll connect the aircraft & remote and nvidia shield and report back.

Happy Holidays!

Roilling in the deep?
I have reached -473 feet altitude. Never though using a drone for mining industry would be beneficial. Here we go.

berkay Posted at 2016-12-26 08:44
Roilling in the deep?
I have reached -473 feet altitude. Never though using a drone for mining industry would be beneficial. Here we go.

Read post #7 above

Thank you.