Please it is now my 4th flight and my P4 on P, S, atti, turning off obstacles avoidance, etc. drops 3 to 4 meters every time I stop. I have latest firmware, done perfect IMU, etc etc. please DJI fix this issue or I will send the P4 back. By the way I own 3 different P4, I got 2 more for my kids, and they all 3 do the same exact issue. Today I had to fly back my P3pro to enjoy the day, no problems or issues whatsoever. If not fixed by this week I will return all 3 Phantom 4 back. Please be so kind to reply with a upcoming solution. Every forum I went on everybody is having same exact issue. Thx.

You will be returning your P4 then. This is a user forum, meaning it is for users to help other users. DJI do not always come here and they also do not respond to ultimatums or threats.

I've seen this issue in another thread and would like to pass it to our developers. We will keep making improvements of our products to satisfy customer's needs, but I will need your help. Please upload your flight data to the Dropbox, and send me a link. Our R&D guys will analyze it and try to find out the solution. Thank you !

if i get time ill try an upload my data in next few days as mine dropped so far it nearly hit the ground. i may need help in how to upload though

I have the Same problem , when I stop droop around 2 or 3 meter , almost crashed , I hope the fix this

I'm also experiencing altitude drop after stopping.. I have the latest firmware..

Me too i think that is a serious problem

DJI Phantom firmware updates now a days have a really serious issues

DJI-Tim Posted at 2016-4-11 05:00
I've seen this issue in another thread and would like to pass it to our developers. We will keep mak ...

It is hard to believe that this prevalent issue was not noted during DJI's own development and testing.  

If it wasn't then they didn't test enough or changed something in the production birds.

If it was detected during testing and they still haven't fixed it; then it makes on wonder if they can without a hardware solution.

I haven't flown with this firmware yet, but on the previous one I noted that if flying forward then stop, the PS4 dropped altitude. If I flew backwards then stopped, it gained altitude instead. I wrote about this earlier in a thread.

For those of you that have flown with the newest firmware, how did it behave when flying backwards and then stop?

I crashed my Phantom 4 today after it dropped after finishing a Waypoint run.  Thankfully no (major) damage done, this was after it flew into a small bush when using active track and broke two props.  I already have two sets or props on order from Apple (they don't charge the horrendous £10 shipping that the DJI store wanted) so they'll be put to good use by the looks of it.

I had thought the altitude drop was normal behaviour until I looked here on the forum.  Any chance this will be getting fixed soon with a new firmware release?

I have the same issue with losing altitude as well. You can check out this video that someone reviewed the P4 and you can see it literally drop in altitude.

I had my P4 out on Saturday and when I stopped it dropped right into a tree. Major damage was done.

DJI-Tim Posted at 2016-4-11 05:00
I've seen this issue in another thread and would like to pass it to our developers. We will keep mak ...

This has been reported before, why hasn't the problem been fixed by now?  Is DJI going to replace P4s damaged by this flaw?

DFWdude4DJI Posted at 2016-4-11 11:06
I have the same issue with losing altitude as well. You can check out this video that someone review ...

Great job and great video, that is exactly what my P4 is doing. Thank you for helping showing what everybody are experiencing with the Phantom 4. I truly hope DJI will fix this major issue very soon.

I have noticed the drop as well, and it can be scary.    It is perhaps even more noticeable because the other flight characteristics are astonishingly true to command, even in gusty wind (other than my one experience with a low hover over fast moving stream).   Hopefully DJI will fix this with firmware.

There are two other threads on this here that have had flight logs listed me being one I think it's time to do the official dji support log the get things moving, I'll do one I think others need to do it too that way they will have to do something

Ok, is the elevation controlled by a barometric pressure sensor? If so, could the new fan that they've installed in this P4 be the cause? Constantly moving air through the inside of the P4 would cause this no?

skyline_g35@msn Posted at 2016-4-11 22:45
Ok, is the elevation controlled by a barometric pressure sensor? If so, could the new fan that they' ...

No.  Why would stopping have any impact on the effect of a running fan?

DJI-Tim Posted at 2016-4-11 06:00
I've seen this issue in another thread and would like to pass it to our developers. We will keep mak ...

                 

DJI-Tim,
Do you work with DJI-Ken? He also asked me for a video and I sent him the link 2 days ago.

  

Not just me but a ton of users have been uploading videos all week long. This is not the first user that is complaining. How long do we have to beg to DJI-Gods so they acknowledge the problem. Go search any post related to this issue and will find almost none for the Phantom 3. Phantom 3 had more issues related to video feed loss and cracks than anything else. I know b/c I bought the first batch in June last year. My second update I noticed loss of signal.

  

  

Deja-Vu, Phantom 4 has this height drop problem, period. How long would it take for a multi-billion dollar company get 3 geniuses from HQ to figure it out? or at least let us turn off the VPS (in case some thinks that's the issue here)

  

  

P4 does look as beautiful like an apple product, congrats. But to become the "APPLE" of the sky's, the entire organization must treat their customers with respect, accountability and transparency.

  Almost forgot, here goes one more video...

parkgt Posted at 2016-4-12 01:12
This has been reported before, why hasn't the problem been fixed by now?  Is DJI going to replace  ...

We need the flight data to analyze it.  My P4 doesn't drop the altitude. Could you please post flight data if it's losing altitude if your drone is losing altitude

DJI-Tim Posted at 2016-4-12 07:20
We need the flight data to analyze it.  My P4 doesn't drop the altitude. Could you please post fli ...

Hi Tim

heres one if you need more please let me know

https://www.dropbox.com/s/fca71u ... 3-08-06%5D.DAT?dl=0

also just because you not seeing it on your bird there are planty of users on here that it does please take this as a importent bug, with a P4 that this happens on you have to compensate everytime you fly over something and need to stop for say a POI

DJI-Tim Posted at 2016-4-12 14:20
We need the flight data to analyze it.  My P4 doesn't drop the altitude. Could you please post fli ...

Here are some records from me as well.  I've posted them prior and also submitted a support ticket but never got a response.  

Would be great if you could have a look and post some feedback here or to the open support request.

https://onedrive.live.com/?id=9C ... id=9CF0FBFD85DEA5C7

stshields91 Posted at 2016-4-12 22:42
Here are some records from me as well.  I've posted them prior and also submitted a support ticket ...

Thank you ! We will be working on it.

DJI-Tim Posted at 2016-4-12 15:06
Thank you ! We will be working on it.

great thanks tim

DJI-Tim Posted at 2016-4-12 10:06
Thank you ! We will be working on it.

My 14 days return from purchase are over tomorrow. I will be returning my 3 units of Phantom 4, my neighbors are returning theirs, we are talking about approximately 14/15 Phantom 4. I stopped by Apple today and they told me they are having too many complaints and large amount of returns on the P4. Several people upset!! Including the store manager!! Which is a good friend and in conference he told me: "Not sure this is lasting if it continues with returns after returns and people getting upset at Apple". DJI is a great company but this P4 it might not be ready software or hardware wise. It looks great, but it is not even close to work as good as it looks. DJI-Tim when you are done working on it, or you have any news, let me know so I will try buying it again. Thank you.

Topviewpics Posted at 2016-4-12 13:00
DJI-Tim,
Do you work with DJI-Ken? He also asked me for a video and I sent him t ...

Yes, we are working on this issue right now.
I noticed one thing... you are flying in the same location where the Verge was recording his Phantom 4 review ...?

DJI-Tim Posted at 2016-4-13 02:31
Yes, we are working on this issue right now.
I noticed one thing... you are flying in the same loc ...

It will be very telling if Apple drops the P4 due to excessive returns.

The one positive from this is that it may put more pressure on DJI to resolve some of the issues than any individual owner can bring to bear.

It will be hard for DJI to ignore Apple.

Do they ALL do this, or just some of them? Is there any known correlation between the P4 versions with or without the gimbal guard positioning marks? Any known serial number range or other indication? Mine did it on it's third flight and scared the wits out of me. It dropped about 15 feet and I thought it was pilot error. Only four days old, so it may go back and I'll reorder when this Major problem is fixed.

My P4 does it as well.  Even after calibrating the vision sensors via Assistant 2 (and calibrating IMU, compass), it still persists.

On one flight, it dropped a good 6 feet and finally stopped about 3 inches from the ground, then rose back up.  

Same problem here, noticed two random drops that I was aware of on its second flight, latest updates done. Flying on android device.

DJI do you require more flight logs, or do you have enough already to provide answers ?

I have experienced a small drop when stopping due to object avoidance.  The craft was travelling at about 7m/s.  The flight was about 5m above the start point but due to increasing elevation the ground it was only about 1.5m above the ground at the end.  When the craft stopped it dropped about 1.5m and almost hit the ground before rising up again by about 0.5m,  The flight log shows the barometric elevation above home at about 4.9m at the start of the flight and at about 5.0m just before the avoidance stop, dropping to 4.7m before rising to 5.2m.  This variation in barometric altitude is probably within the error range of the barometric sensor and there doesn't appear to be a significant drift over the 1km length of the flight.  So I don't see the drop on stopping being due to barometric elevation drift but perhaps is due to braking action not compensating enough for the gravity when stopping.  It looks at if the VPS did cut in at the end and raised the craft just before it hit the ground.
In the video, stop occurs at about 16 secs (I've slowed down the video speed to 50% just before stop)

An interesting bit of evidence would be how much does it drop vs. the forward velocity before the stop command.  When stoppling from a high forward velocity (copter is pitched forward) requires a sudden drop in collective pitch to prevent a sudden rise. This is because when pitched over at high speed the collective power is high to maintain altitude. Barring some other HW issues, it sounds like the control laws have too much integral gain relative to differential, so the thing reacts too slowly. The collective power control does not respond quick enough. Makes for stable flight only when moving slowly. What made me think of this is that I'm flying in cool, high density air (so rotors have some extra bite on the air, and motors are not maxed out, crudely speaking)  and I generally fly relatively slow before a stop command so that the copter stays within its comfortable control range. I dont see much in the way of dropping. Sounds like DJI folks are flying faster and not getting serious drops though, so I dont know... Until the issue is resolved one may want to avoid rapid maneuvers before stopping, i.e. come to a stop slowly.... to avoid becoming a statistic...

DJI-Tim Posted at 2016-4-12 14:20
We need the flight data to analyze it.  My P4 doesn't drop the altitude. Could you please post fli ...

How do I get the flight data for you to analyze? Where do I go to retrieve them?

I am having the same issues with loosing altitude after stop with my P4 .  As much as 6 feet.  Was hoping the firmware upgrade might fix it but from other post it doesn't seem to.
Even in a hover it will fall a foot or more.  Never had this issue with Phantom 3pro. I am a few days out of my Apple return period but am considering trying to return due to defect.  Lucky my Phantom 3 is still fun to fly cause the P4 is not.

DJI-Tim Posted at 2016-4-13 03:31
Yes, we are working on this issue right now.
I noticed one thing... you are flying in the same loc ...

Yes, it is the same place. And that's were my P4 keeps dropping height from forward flight and increasing height from flying right to left, followed by drop too. That's my major hiccup with this unit. On the other hand, video signal has been great compared to my previous P3Pro flying in the same exact area.
PLEASE have DJI fix this issue and add VPS on/off and DJI will be making all of us happy!

FatedFilmsNC Posted at 2016-4-13 19:43
How do I get the flight data for you to analyze? Where do I go to retrieve them?

Use the dji assist program on a PC and connect the P4 and its under flight data

kim.elitepp Posted at 2016-4-13 15:02
I am having the same issues with loosing altitude after stop with my P4 .  As much as 6 feet.  Was h ...

My phantom 4 appeared to be losing altitude when I stop as well but after a few flight I noticed that when it brakes it accually climbs around 6 feet while its stopping then drops around 6 feet to its original altitude.

scfilmvideo Posted at 2016-4-13 23:26
Do they ALL do this, or just some of them? Is there any known correlation between the P4 versions wi ...

All the P4s do this and countless other issues have also been reported and noted.
There is truly a lot of software or hardware issues that need to be rectified asap....