Mavic Pro dropped out of the sky

[orange775]

Just wanted to give my update. I was quite surprised with dji after sale support, after sending in my broken mavic, after couple of days they received the drone they automatically took the responsibility of fixing it without zero cost.

 

[Alex.ter]

I'd like to look at the flight logs like Robbyg. The DATs are preferable, but the TXTs will do. This is the fourth incident of a new Mavic dropping out of the sky.

Mine just dropped today, disconnected from controller and I looks up and see it falling, lights were still on, on the mavic, I just have logs from controller, lost the mavic really hope dji will replace it for free, because this wasn't my fault

 

[flyNfrank]

Mine just dropped today, disconnected from controller and I looks up and see it falling, lights were still on, on the mavic, I just have logs from controller, lost the mavic really hope dji will replace it for free, because this wasn't my fault

You really should pull the TXT and DAT flight log files. I can analyze the data for you if needed. There is no reason for the A/C to drop if communication is lost between the A/C and R/C. You can shut the power off to the R/C and the GO4 app while in flight and the A/C will not drop. It will run in FailSafe Mode. It depends on which failsafe mode setting you had selected will determine how the A/C responds. For the A/C to suddenly drop, it would be a broken prop, motor, or ESC issue. I would have inclused connection with battery but since you stated the lights were still on, I didn't add the battery to the list.

Are you able to retrieve the files?

 

[Alex.ter]

You really should pull the TXT and DAT flight log files. I can analyze the data for you if needed. There is no reason for the A/C to drop if communication is lost between the A/C and R/C. You can shut the power off to the R/C and the GO4 app while in flight and the A/C will not drop. It will run in FailSafe Mode. It depends on which failsafe mode setting you had selected will determine how the A/C responds. For the A/C to suddenly drop, it would be a broken prop, motor, or ESC issue. I would have inclused connection with battery but since you stated the lights were still on, I didn't add the battery to the list.

Are you able to retrieve the files?

I found the Mavic today, pulled the txt file and DAT file, dat file is incorrect but txt is correct, when I get home I'll upload the correct DAT file


MEGA

 

[flyNfrank]

I found the Mavic today, pulled the txt file and DAT file, dat file is incorrect but txt is correct, when I get home I'll upload the correct DAT file


MEGA

I looked over the two TXT files you included in the zip. Everything looked ok except the Battery data. Something is seriously messed up in that area.

 

[Alex.ter]

I looked over the two TXT files you included in the zip. Everything looked ok except the Battery data. Something is seriously messed up in that area.

Ouch, what exactly is wrong?

 

[sar104]

Ouch, what exactly is wrong?

Unless I'm missing something, the DAT file (FLY047) and the txt file (DJIFlightRecord_2017-10-24_[18-26-29]) just stop in mid-flight at 400 seconds and 485 ft altitude. No warning at all. That suggests sudden and catastrophic failure of the FC. I'd expect DJI to replace it.

 

[Cyberpower678]

Sorry, I'm not seeing what Frank is seeing. The battery data looks okay. The flight log just abruptly ends mid flight as if the battery disconnected. I see no warnings what so ever. I'd chalk it up to the battery not being securely in place and it momentarily disconnected. PS your drone's Failsafe is set to hover. You may want to check your settings on Remote disconnect.

 

[sar104]

Sorry, I'm not seeing what Frank is seeing. The battery data looks okay. The flight log just abruptly ends mid flight as if the battery disconnected. I see no warnings what so ever. I'd chalk it up to the battery not being securely in place and it momentarily disconnected. PS your drone's Failsafe is set to hover. You may want to check your settings on Remote disconnect.

I agree that the battery looks fine, but I don't think that it was just a battery disconnect. Other DAT files, where that has clearly happened, record a clear voltage sag as the disconnect occurs, lasting a tenth of a second or so. No sign of that here. I suspect some other failure that also terminated logging instantly.

 

[Cyberpower678]

I agree that the battery looks fine, but I don't think that it was just a battery disconnect. Other DAT files, where that has clearly happened, record a clear voltage sag as the disconnect occurs, lasting a tenth of a second or so. No sign of that here. I suspect some other failure that also terminated logging instantly.

I wouldn't put stock in that. It could have been a latent charge that allowed to computer to still log a bit. Ultimately if it is a HW failure, DJI diagnostics will definitely find it when the run the board for testing.

 

[sar104]

I wouldn't put stock in that. It could have been a latent charge that allowed to computer to still log a bit. Ultimately if it is a HW failure, DJI diagnostics will definitely find it when the run the board for testing.

Agreed - they should be able to determine the cause. If by "latent charge" you mean that there is capacitatively stored energy on the power board then yes - that's going to be exactly what causes continued logging and detectable voltage sag as it discharges, and it should always occur like that, hence my comment.

 

[Cyberpower678]

Agreed - they should be able to determine the cause. If by "latent charge" you mean that there is capacitatively stored energy on the power board then yes - that's going to be exactly what causes continued logging and detectable voltage sag as it discharges, and it should always occur like that, hence my comment.

My point is that flying in Sport mode means a higher power draw, meaning a faster capacitor discharge, meaning it could've discharged so fast it didn't log. The drone was flying full throttle in Sport mode when the log ended. So while it always discharges, the drone uses 2 times the current flying in Sport mode than it does in P mode. Same HW different power consumption conditions.

 

[sar104]

My point is that flying in Sport mode means a higher power draw, meaning a faster capacitor discharge, meaning it could've discharged so fast it didn't log. The drone was flying full throttle in Sport mode when the log ended. So while it always discharges, the drone uses 2 times the current flying in Sport mode than it does in P mode. Same HW different power consumption conditions.

All good points, although based on previous files, even twice the current draw would not kill it fast enough. The motor data are logged at 50 Hz.

 

[Porto]

PS your drone's Failsafe is set to hover. You may want to check your settings on Remote disconnect.

I wouldn't be surprised if he did set his remote disconnect to RTH. When I looked at my DAT files that has been converted to csv, I was surprised to see my remote disconnect was set to Hover even though it was never been set to other than RTH. The drone also never fails to RTH on remote disconnect. When I checked the setting, it was indeed set to RTH.

Something could be wrong in the conversion to csv.

 

[BudWalker]

I wouldn't be surprised if he did set his remote disconnect to RTH. When I looked at my DAT files that has been converted to csv, I was surprised to see my remote disconnect was set to Hover even though it was never been set to other than RTH. The drone also never fails to RTH on remote disconnect. When I checked the setting, it was indeed set to RTH.

Something could be wrong in the conversion to csv.

I've seen this. But, what seems to happen is that RC:failSafe gets the right value only when the disconnect happens.

 

[Siwyleeds]

Mate I believe you. It happened to me but a bit a bit different. Actually I took off froma. Golf's green, was flying around and brought it back to land and about 1 meter up push the stick down to land and bam hit the green and bounced.

The motors shut down as if it had already landed. I was lucky it was a very soft green so just got the back props chipped and didnt hit the gimbal.

So I opened a case with DJi they reviewed my logs and the outcome of the investigation was that the below facing cameras got confused because of the "solid" colour.

Your case might be the same so push them under warranty.

I bet You’ve last a confidence after this one.

 

[Siwyleeds]

Those are very good machines but if You’ll go through all different models the most problematic one. I’ve been using my p3a for over a year. No problems what so ever. After buying the mavic i was really suprised seeing posts about fly aways loss of connections etc. I’ve got my insured just in the case.

 

[Porto]

I've seen this. But, what seems to happen is that RC:failSafe gets the right value only when the disconnect happens.

Now that explains it. Thanks!

 

[Alex.ter]

But the mavic flew an extra 50 feet after the log ended and before it started falling, and it was falling fast but the props were still spinning fast enough to keep the mavic up right and not tumbling, also leds were still on, as much as I thought it was a battery disconnect I don't think it is

Sorry, I'm not seeing what Frank is seeing. The battery data looks okay. The flight log just abruptly ends mid flight as if the battery disconnected. I see no warnings what so ever. I'd chalk it up to the battery not being securely in place and it momentarily disconnected. PS your drone's Failsafe is set to hover. You may want to check your settings on Remote disconnect.

 

[Alex.ter]

But the mavic flew an extra 50 feet after the log ended and before it started falling, and it was falling fast but the props were still spinning fast enough to keep the mavic up right and not tumbling, also leds were still on, as much as I thought it was a battery disconnect I don't think it is

Also I don't know how you see fail safe set to hover, after the crash I went into the app and checked and it was set to RTH