Battery dropped from 53% to 0% ,almost lost my MA

[Benmoore1234]

Hi,I got a MA on Tuesday. I spent a few days reading through the instructions,charging,updating and just getting to know my new toy.i took it out on Friday morning to give it a test and the strangest thing happened. I was flying around at around 53% then suddenly the battery went to 0% and started to land,controller kept disconnecting.i started running over the field to get to it,I managed to land it safely. The battery appeared flat on the led indicator on the battery. So I decided to try my second battery and the same happened around the same battery percentage.
So I uploaded the flight records to air data. Everything seems to be ok till it happens. This isn’t my first Dji product,I had a phantom 3 advanced so I don’t think I’ve made any silly mistakes. Started the flight at 100% ,calibrated the compass ,connected to gps ,phone charged,weather was pretty calm 5deg,home point set . Seen this issue a few times on the Dji forum but nobody seems to have an idea. I don’t really think it’s a battery issue,or I could be really unlucky and have two bad batteries. Please take a look at my flight logs an see if I’ve missed anything. Seems like software issue but can’t really prove it.
Thanks

Airdata UAV - Flight Data Analysis for Drones

Airdata UAV - Flight Data Analysis for Drones

 

[Travisimo]

Interesting... I too find it very difficult to believe you have two new batteries that are defective. In looking at your first log, it appears that the troubles start at 08m11s, right after you switched to Sport mode. You got a critical low battery warning, followed by a motor overload, and then you lost connection (not a good combination). Looks like you were able to re-establish communication and eventually landed at 13m42s, quite some distance away from your home point (as you mentioned). The log shows battery percentage of 54% at 09m22s, which sounds about right where it should be at that flight time (but that is after it already gave you a critically low battery warning). So it's clear that your actual battery was not at 0% (even at your final time of landing, it would not have been at 0%).

In the second log, you got an initial warning about low battery temperature. What were the conditions you were flying in? And again, it looks like your trouble begin shortly after switching to Sport mode (second time during this flight). Doesn't look like you got the motor overload errors that time, but at 08m54s, you had 53% battery, which again sounds about right for that flight time. So when you landed at 09m25s, your battery level was most certainly not 0%.

Now let the experts tell you what went wrong... my guess is that it has something to do with the temperature of the batteries and sport mode causing too much power draw.

 

[Benmoore1234]

Interesting... I too find it very difficult to believe you have two new batteries that are defective. In looking at your first log, it appears that the troubles start at 08m11s, right after you switched to Sport mode. You got a critical low battery warning, followed by a motor overload, and then you lost connection (not a good combination). Looks like you were able to re-establish communication and eventually landed at 13m42s, quite some distance away from your home point (as you mentioned). The log shows battery percentage of 54% at 09m22s, which sounds about right where it should be at that flight time (but that is after it already gave you a critically low battery warning). So it's clear that your actual battery was not at 0% (even at your final time of landing, it would not have been at 0%).

In the second log, you got an initial warning about low battery temperature. What were the conditions you were flying in? And again, it looks like your trouble begin shortly after switching to Sport mode (second time during this flight). Doesn't look like you got the motor overload errors that time, but at 08m54s, you had 53% battery, which again sounds about right for that flight time. So when you landed at 09m25s, your battery level was most certainly not 0%.

Now let the experts tell you what went wrong... my guess is that it has something to do with the temperature of the batteries and sport mode causing too much power draw.

Thanks for the input, I didn’t think of the sport mode. Will look at that when I test it out tomorrow

 

[Travisimo]

Thanks for the input, I didn’t think of the sport mode. Will look at that when I test it out tomorrow

Maybe try warming up the batteries before flight and then do a hover test to see how much flight time you get before critical low battery. If you start at appx. 100% and land at appx. 15%, you should get approximately 15-18 minutes of actual in-flight time. The aircraft should be able to handle sport mode in good conditions, but if your batteries are cold, that could cause problems.

 

[Benmoore1234]

Maybe try warming up the batteries before flight and then do a hover test to see how much flight time you get before critical low battery. If you start at appx. 100% and land at appx. 15%, you should get approximately 15-18 minutes of actual in-flight time. The aircraft should be able to handle sport mode in good conditions, but if your batteries are cold, that could cause problems.

Thanks, will pay attention to this on my next flight

 

[mavicn00b]

I found with the MA, if the signal between RC and AC isnt that good, DJI Go 4 doesnt refresh the battery as often and the % indicator can sit at any one point for quite a while. As the signal quality improves, sometimes a huge chunk of battery goes missing as it "updates".

Just something to be weary of, It might leave you stranded thinking you have more battery left then you really did. My Spark and MP didnt have this issue.

 

[Keule]

At the DJI forum there are another 3 incidents where the battery suddenly drops to 0%.
@Benmoore1234 what firmware are you running?

 

[sar104]

Hi,I got a MA on Tuesday. I spent a few days reading through the instructions,charging,updating and just getting to know my new toy.i took it out on Friday morning to give it a test and the strangest thing happened. I was flying around at around 53% then suddenly the battery went to 0% and started to land,controller kept disconnecting.i started running over the field to get to it,I managed to land it safely. The battery appeared flat on the led indicator on the battery. So I decided to try my second battery and the same happened around the same battery percentage.
So I uploaded the flight records to air data. Everything seems to be ok till it happens. This isn’t my first Dji product,I had a phantom 3 advanced so I don’t think I’ve made any silly mistakes. Started the flight at 100% ,calibrated the compass ,connected to gps ,phone charged,weather was pretty calm 5deg,home point set . Seen this issue a few times on the Dji forum but nobody seems to have an idea. I don’t really think it’s a battery issue,or I could be really unlucky and have two bad batteries. Please take a look at my flight logs an see if I’ve missed anything. Seems like software issue but can’t really prove it.
Thanks

Airdata UAV - Flight Data Analysis for Drones

Airdata UAV - Flight Data Analysis for Drones

You didn't enable download of the original log files, so it is difficult to provide any useful feedback.

 

[Benmoore1234]

At the DJI forum there are another 3 incidents where the battery suddenly drops to 0%.
@Benmoore1234 what firmware are you running?

Whatever is the latest and greatest, the app said everything was good before I took off. I connected ma to the assistant 2 to check for updates and everything was good. Yeh I’ve seen the ones in the Dji forum.strange

 

[Benmoore1234]

I found with the MA, if the signal between RC and AC isnt that good, DJI Go 4 doesnt refresh the battery as often and the % indicator can sit at any one point for quite a while. As the signal quality improves, sometimes a huge chunk of battery goes missing as it "updates".

Just something to be weary of, It might leave you stranded thinking you have more battery left then you really did. My Spark and MP didnt have this issue.

I know what your saying,in this case I don’t think that has happened.

You didn't enable download of the original log files, so it is difficult to provide any useful feedback.

not sure what you mean. Is that something I can do in air data

 

[sar104]

not sure what you mean. Is that something I can do in air data

Yes. Or just post the txt log here.

 

[Benmoore1234]

Yes. Or just post the txt log here.

Could you help me,not sure what it is your wanting. Is it the file I uploaded to air data

 

[Kilrah]

Yes.

 

[sar104]

Could you help me,not sure what it is your wanting. Is it the file I uploaded to air data

Yes - the original .txt file that you uploaded to Airdata is what is needed.

 

[BIGLUG24]

Did you charge the battery's 100% before useing. Also there was a update for something like that you may want you
do a refresh on your firmware. I saw a video where this happen and he had not did the update.

 

[Benmoore1234]

Yes.

 

[Benmoore1234]

Did you charge the battery's 100% before useing. Also there was a update for something like that you may want you
do a refresh on your firmware. I saw a video where this happen and he had not did the update.

Yes batteries charged to 100% and all firmware was up to date. Status of the ma was normal.

I’ve since reinstalled the firmware with assistant 2 , reinstalled the app,charged batteries,calibrated imu and compass and tested today. No issues what so ever. Maybe just a one off,

 

[BIGLUG24]

Happy to hear your up and flying Have a great day

 

[laurens23]

I looked at both .txt files. this looks exactly like another user posted.
in all three cases it happened around at the same battery % at almost exactly 8 min flight time.

 

[Kevjones777]

I looked at both .txt files. this looks exactly like another user posted.
in all three cases it happened around at the same battery % at almost exactly 8 min flight time.

I agree ---- coincidence ? I dont believe in coincidences. I think this could be happening a lot more than is reported here. Only a handful of pilots actually join this forum.