Experienced drone pilot. Own multiple DJI drones. New phantom 4 Pro, little windy, have successfully flown in far worse. Using RTH Drone gets above landing area starts it’s automated decent. During its decent, it flipps completely over, goes inverted and pile drives itself at full RPM into the ground. Complete distuction. I’m bewildered. New drone, everything calibrated properly and flying autonomously in RTH mode. This appears to be a very expensive glitch. Can someone tell me what happened?

Sent flight record to DJI. Don’t know how to post it here.

Check out the flight log and see if it explains what happened. You can upload and view the TXT flight log online here. Post a link back here after uploading it if you'd like other people to review and comment on it.

Figured it out.

http://www.phantomhelp.com/LogViewer/NI47KBCTITYXJ0XK4QLC/

At 6:18 it started tumbling and rapidly falling. Maybe someone else can say why.   I saw nothing that could suddenly cause that, unless it was a bird strike or something.   

To say your battery appeared a tad wonky ( a technical term ) is an understatement.

A minute in, and in sport mode full throttle and your battery was already under 3.6vdc/cell........for a long time.

Cell deviation is a bit high, but have seen it before.....not related to a crash.

You are inside 3 miles of KJKA  Edwards National......in the flight path for take off,   or final....at 780ft AGL      THAT'S ILLEGAL IN THE UNITED SATES.

Please set your MAX Altitude setting to 120m,  and please don't fly in the flight path of an airport.  Keeping your AC below 100ft AGL that close to an airport would be responsible.

Please learn where and when you can fly, as well as how high before you fly again.....please,  before you hurt someone.
BTW,  your stick movements toward the end were very erratic.......is it possible you spit a blade off the AC?  As that would account for the tumble.....

Randy

rwynant V1 Posted at 2018-9-4 13:16
To say your battery appeared a tad wonky ( a technical term ) is an understatement.

A minute in, and in sport mode full throttle and your battery was already under 3.6vdc/cell........for a long time.

I was fully authorized to fly. We are under hurricane warning here and airport is under a TFR. I was with a FEMA rep and the Mayor of OB getting a visual of off shore weather activity. Not illegal, but thanks for looking out. Still have no clue what happened.  

No bird strike. I was under VFR at time of Wonky-ness.

RANDY,
All blades are accounted for. Interesting theory though. It was an incredibly violent landing, so im unable to determine the condition of blades prior to impact. I suppose its possible that the blade broke in flight. Do you think its more likely then the DJI getting "confused" and going Wonky?  

My stick movements were erratic at the very last 2 seconds while trying to regain control of aircraft. other then that smooth flight.

Jason.a.Bearden Posted at 2018-9-4 13:48
I was fully authorized to fly. We are under hurricane warning here and airport is under a TFR. I was with a FEMA rep and the Mayor of OB getting a visual of off shore weather activity. Not illegal, but thanks for looking out. Still have no clue what happened.

The FAA governs the NAS  ( National Airspace )  Not the mayor or FEMA fergodsake.....

You were also operating in a Military Operations Area.

As for your stick movements,  Yup I get that......try everything!   So now,  on to your battery......was this the first flight with that battery?

Randy

As I have stated in other threads,  LiPo ( Lithium ) batteries NEED to be cycled before complete power is available.  Cycle 4 to 6 times with reasonable flight characteristics.

The voltages reported towards the end were not that bad..... 3.6ish VDC/cell......but the available amps required to run 4 esc/motors and all other electronics may not have been there........

EG;  Car battery that is "iffy"    Starts your engine kinda slow......but it starts.....but if you have your headlights on, that draws just enough that the battery will no longer turn the starter.....it's all Load Related.

But it will be interesting to hear what DJI says.......hopefully they'll replace your bird!!!  Really, I hope so......so let us know when this all sorts out.

You have an FAA Authorization to fly in CL D airspace?  Either a Hard Copy, or LAANC Authorization?    If you do have an FAA Auth,  then your max AGL would have been about 150 to 200ft ( I can only est. )
And this would also mean you have an FAA Part 107 Certificate...?
Fly Safe

Randy

rwynant V1 Posted at 2018-9-4 14:33
As I have stated in other threads,  LiPo ( Lithium ) batteries NEED to be cycled before complete power is available.  Cycle 4 to 6 times with reasonable flight characteristics.

The voltages reported towards the end were not that bad..... 3.6ish VDC/cell......but the available amps required to run 4 esc/motors and all other electronics may not have been there........

How do you cycle the batteries?

And Jason,   keep your head down!!  Looks like that storm is closing in fast.........

All the best

Randy

Christine96 Posted at 2018-9-4 14:43
How do you cycle the batteries?

Full charge and full discharge = 1 cycle

If you only bring a battery down to say 50% and then re-charge to 100% that is only considered a half cycle.

Cycle Batteries

Fully Charge,  fly within a day or 2   But fly easy.....cruise around 15 - 20mph  climb easily,  not using full throttle....run down to 30% and land

Let cool completely.......recharge and do it again to 30%    then twice to 20%.....one key,  Is COOL the batts after use and before recharge.

BTW I was looking again at your flight log......cell number 4 might be an unhappy cell.  Keep an eye on that battery and cell voltages.  Please read up on Lithium Battery Care

After a crash like that, I would be very cautious with that battery, if you keep it.

Randy

No problem with that. lol

Edwards National?   Military operations area?  I am very familiar with this area, and it's made out to look like  area 51 lol.   It's NOT.   Other than going a little higher than you should, you did nothing wrong.

Is there any way to test your batteries for problems?  

Jason.a.Bearden Posted at 2018-9-4 12:21
Figured it out.

http://www.phantomhelp.com/LogViewer/NI47KBCTITYXJ0XK4QLC/

First up, the battery was fine and there's no hint of anything that would cause a problem there.

I do see something odd with the VPS readings but nothing that should have caused the incident.
It appears normal on launching except it is reading up to 20 metres?
At 1:17.8 and 238ft the VPS is showing 15 feet for 1.5 seconds.
Again at 1:35.3 for 3 secs, 1:53.8 for 5 secs, 3:09.1 for 6 secs, 3:25.4 for 9 secs, and more.
I'm not sure what's going on there.

Up until 6:17.7 the Phantom is in stable descent for autolanding.
But here it starts to wobble and roll and fall.
The compass errors are likely to be related to the movement of the Phantom rather than a genuine compass issue.

I would suspect you have a genuine hardware fault and a warranty claim.
Synch your flight record (click on the cloud icon on your flight records page).
Then go to DJI online support and have a chat with their people to get things started.

Christine96 Posted at 2018-9-4 14:43
How do you cycle the batteries?

DJI batteries don't need to be cycled.

msinger Posted at 2018-9-4 20:10
DJI batteries don't need to be cycled.

I'm hearing both they do and they don't.  I don't know.  Maybe a DJI tech could clarify this if one is reading this thread.  

Christine96 Posted at 2018-9-5 17:36
I'm hearing both they do and they don't.  I don't know.  Maybe a DJI tech could clarify this if one is reading this thread.

Christine ... DJI tech never comes here with any input and the moderators don't even fly drones so they wouldn't have a clue.
You'll hear both ways on many issues on the forum, and half of what you hear is likely to be wrong.
The forum is very successful at spreading rumours and perpetuating myths.


But if Msinger tells you something, you can rely on his input to be accurate.

Christine96 Posted at 2018-9-5 17:36
I'm hearing both they do and they don't.  I don't know.  Maybe a DJI tech could clarify this if one is reading this thread.

You'll hear lots of things on the Internet. You need to figure out who to trust for good sources of information and rely on those people.

Seems like deep cycling batteries can balance the cells, if they require that.


DJI themselves are great at contradictory advices. Particularly where their own intelligent flight packs are concerned.


RedHotPoker

Sorry to read about the OP having a bad day at the rc park.


RedHotPoker

Hi. We apologize for the inconvenience. Did you see any error message appeared on your app?

Update. I’m a bit shocked on how easy this was. It appears as DJI has stepped up their customer service. Impressed.

That’s brilliant..

Good news, thanks DJI!! Good on you.


RedHotPoker

Great news! Glad you will be getting a replacement via DJI!

What was the problem?

Christine96 Posted at 2018-9-20 17:20
What was the problem?

Unless one of the moderators takes a look at the case file and comes back and lets it slip we will never know.   Sometimes if its a repair and not a replacement you can make an educated guess based on parts replaced.

Christine96 Posted at 2018-9-20 17:20
What was the problem?

It broke lol
Thats all we ever know

Well in technical terms they determined the aircraft got confused. Just a simple glitch with catastrophic results. I’m sorry, but apparently there isn't a lesson that we could all learn to avoid it from happening again. For “entertainment”, here is a picture of what happens to a Phantom when it goes inverted at full throttle from 160’ to impact.

Here is a fun fact though. My Phantom aircraft is the first one to ever exceed a documented speed of over 120 mph. I hope none of you ever break that record.

Jason.a.Bearden Posted at 2018-9-21 05:01
Well in technical terms they determined the aircraft got confused. Just a simple glitch with catastrophic results. I’m sorry, but apparently there isn't a lesson that we could all learn to avoid it from happening again. For “entertainment”, here is a picture of what happens to a Phantom when it goes inverted at full throttle from 160’ to impact.

That scares me because a lot of times there are people in the area of these things.  

Christine96.... Precisely my thoughts

Most likely some circuit just said "I quit".   Everytime I get something new that is electronic I tend to use the heck out of it in the beginning to see if there will be an early death of any component.   And during that time if its RC related I try and do it where it can cause the least harm if it fails.  If it makes it thru an hour chances are it will have a long and useful life.

Update! New aircraft arrived in the mail today! Fast turnaround and best part...cost=$0.00 Thanks for everyone’s input.