Hi,

This is to inform that we have a P4 RTK purchased from USA from dronenerds.com in April 2019.

On 19th Dec during a mission flight there was a sudden loss of power and the drone dropped from 90m.

THe 1st flight was good and after a battery change the mission was resumed. upon climbing vertically to attain the 142m height as per mission planned.
There was sudden aircraft disconnect notice on the app at 90m and the drone dropped down like a brick with major damage to gimbal, camera and top shell including the RTK gps cover.

The battery was firmly locked in place and there was no reason for a power loss. Upon close observation we found the battery terminals in the P4 drone having a blacking smear of plastic. The battery too shows plastic melting at the connection. Attaching pics for your examination.

Also the logfile screenshot which shows drop in voltage and current.

kindly advise.

We have seen this happening to a number of P4's.  Flight records probably show a sudden loss of power.  I believe DJI has been making good on most.

You are in India.  Probably the governments are testing stuff on your drone from space.  Probably sending signal instructions down to the drone making it malfunction.  They won't test it on the people in the United States.  Someone in New Zealand or somewhere definitely had his drone shot out from the sky.

AntDX316 Posted at 1-2 20:19
You are in India.  Probably the governments are testing stuff on your drone from space.  Probably sending signal instructions down to the drone making it malfunction.  They won't test it on the people in the United States.  Someone in New Zealand or somewhere definitely had his drone shot out from the sky.

WARNING: Extreme Bullsh*t Interference. Do not listen to anything this dipsh*t says.

Geebax Posted at 1-3 00:49
WARNING: Extreme Bullsh*t Interference. Do not listen to anything this dipsh*t says.

You don't know what happened any more than I do.

AntDX316 Posted at 1-3 02:47
You don't know what happened any more than I do.

Read and understand the flight log screenshot in post #1!

Keule Posted at 1-3 03:36
Read and understand the flight log screenshot in post #1!

I assume it was a DJI battery and not a knock off

Hey Sandeep,

This is going to sound like a conspiracy theory.  But we had a P4RTK (our first out of 11 units) go down on the 19th of December.

It appears to be a sudden loss of power, same as yours.

I am only back into work today after holidays and will be trying to get the flight log off.  Will keep you posted.

Hey Sandeep,

My drone crashed yesterday during a pre-planned flight mission of 30m. Flight log reported sudden loss of voltage at aprox. 60% battery. I bought the drone last March and have performed less than 20 flights, so I haven't even gotten a return on the investment. I opened a repair ticket, and will keep the forum posted regarding DJI's conclusion. A screen cap of the flight log is shown below.

Given that 3 P4 RTK drones (that we know of) have experienced sudden voltage drops and crashed within the pasted few weeks, I strongly advise other pilots to exercise EXTREME caution until a better explanation for the sudden shutoff is made, and a resolution is discovered to prevent other drones from free falling without warning.

fansbcb29bc3 Posted at 1-5 14:04
Hey Sandeep,

My drone crashed yesterday during a pre-planned flight mission of 30m. Flight log reported sudden loss of voltage at aprox. 60% battery. I bought the drone last March and have performed less than 20 flights, so I haven't even gotten a return on the investment. I opened a repair ticket, and will keep the forum posted regarding DJI's conclusion. A screen cap of the flight log is shown below.

Sorry to hear you lost a second unit.

Did you see any arcing near the battery terminal like pictured above on the second unit?

Hey Sandeep,

What was the time of your incident?  Ours occurred at approximately 4pm AEST.  Which would be around 11:30am in India I believe.

Cheers,

Skyveyor112 Posted at 1-5 15:24
Sorry to hear you lost a second unit.

Did you see any arcing near the battery terminal like pictured above on the second unit?

Nope. No burnt plastic or any scorch marks to point suggest any arcing. The battery did, however, separate from the drone after impact. So in Sandeep's case, if the battery separated from drone after impact like mine did, the arcing in his case could have been caused by the separation of the battery and not during the flight.

Hey fansbcb29bc3,

Our failure occurred at 100m, 7m56s into the flight.  64% battery.  We do not see the sudden voltage drop in the log.  It shows all good at time of failure, all cells balanced and operating normally.

However, I had to get the log off the controller, as I cannot get the log off the drone successfully due to the damage.

We have our supplier raising a warranty request with DJI, will keep everyone posted.

What firmware version were you both operating?

Cheers,

DJI4Survey Posted at 1-5 17:57
Hey fansbcb29bc3,

Our failure occurred at 100m, 7m56s into the flight.  64% battery.  We do not see the sudden voltage drop in the log.  It shows all good at time of failure, all cells balanced and operating normally.

"Our failure occurred at 100m, 7m56s into the flight.  64% battery.  We do not see the sudden voltage drop in the log.  It shows all good at time of failure, all cells balanced and operating normally."

That is pretty much what happens with a connector failure, everything looks OK up until the whole aircraft shuts down. And it won't write anything about it in the log because the whole thing is suddenly without power. The connector issue has been around for several years, and is isolated to the P4 series aircraft. The previous model, the P3, had a much more robust spade connector design for the battery connection. If you go back over earlier posts on this forum, you will see quite a lot of photos of melted connected and burnt connections, just like the photos in thisa post, only worse.

Hey Geebax,

Thanks for the heads up.  It looks to be the connector issue as you mentioned.  OEM battery.  Burnt connections present.  Under warranty, so fingers crossed should be a straight swap.  

Gimbal, legs and shell cactus.  

Being a P4RTK, will be interesting to see if they are less inclined to replace.

Cheers for the help.

DJI4Survey Posted at 1-6 16:15
Hey Geebax,

Thanks for the heads up.  It looks to be the connector issue as you mentioned.  OEM battery.  Burnt connections present.  Under warranty, so fingers crossed should be a straight swap.  

I hope they do, because both halves need to be replaced, the battery and its corresponding socket in the body of the aircraft.

DJI4Survey Posted at 1-5 13:31
Hey Sandeep,

This is going to sound like a conspiracy theory.  But we had a P4RTK (our first out of 11 units) go down on the 19th of December.

Hi,

Thanks for writing back and supporting this post. My crash happened at 11:33am IST.

Hello to ALL,

As mentioned earlier I have 2 scenarios to share. Both crashes occurred on 19th Dec2019 one was at 11:33am and the other at 4:55pm. Both he crashes occurred due to the plastic  melting and covering the contacts which result to a sudden power off and resulting in a crash.  The RTK dropped from 90M height and the P4 PRO dropped from 73m. And strangely the temperature reported is 46deg C for RTK and 67deg C for the P4 Pro.

I request all to check the battery terminals for any signs of melting or deforming due to heat.

THis is the log file from the P4 PRO

DJI4Survey Posted at 1-5 15:52
Hey Sandeep,

What was the time of your incident?  Ours occurred at approximately 4pm AEST.  Which would be around 11:30am in India I believe.

HI,

Yes, you are right its 11:33am IST.

I was able to extract all the Logs from the P4 RTK radio from April 2019 till the crash occurred and results are below.

Skyveyor112 Posted at 1-5 15:24
Sorry to hear you lost a second unit.

Did you see any arcing near the battery terminal like pictured above on the second unit?

Hi,

THis is happening during the flight so its difficult to tell. Also after the crash the damage done is more.
Its only the visual observation on the terminals show that something has happened which lead to the melting of the plastic and resulting in power loss.

The battery is original DJI as can be seen there is serial no printed, need to check with dji database to be sure.