DJI Mavic, Air and Mini Drones
Friendly, Helpful & Knowledgeable Community
Join Us Now

Day 2 on Mavic - failure and crash

I agree it typically does not cause overheating but since the summer is coming up I think people should reevaluate that when the Amb temperatures starts getting up into the high 90's. The cover does cause an increase in temp by several degrees, could be a problem on a very hot day.

Rob
I've always noticed that the fans act appropriately to make sure the boards are at a constant 65 C. After all the fan is what's sucking in the air.
 
I am now thinking, would it be wise to use something like a thin Velcro strap around the body and the battery just as added protection?

If you do that it is going to need to be very thin and I'd think twice about it personally. There really isn't much space underneath, where the strap would have to pass, that doesn't have a downward facing sensor.
 
My Mavic crash was not due to lose battery (according to everything I know). But I really want to defend the users who lost their drones because of a battery coming off in midair.

This is not the first Drone that DJI makes and it seems obvious to me that a locking mechanism should be designed so that it does not allow flying with a loose battery. Anything else would be unsafe and bad product design.

You can’t turn on a microwave with the door open, right! So why should you be able to fly a drone with an unlocked battery?

When users start flying around with Velcro straps abound the body of a $1000 drone just to hold it together during normal use, then I would have to say it has gone too far. :)
 
Personally can't see how a battery becomes loose.
Four reasons possible.
1) Comes out after a crash, you will see obvious damage at the clips.
2) Not clipped in securely before flight, operator error.
3) Worn clips through poor handling, again operator error.
4) Faulty from factory, but surely this would be picked at least by operator when clipping in.
If clipped in securely preflight then how can any flying manoeuvre dislodge it?
I suppose pre flight check should always include proper seating of battery.

Agree with Taus about having some means of making sure all is secure before the motors start, but this would mean another mechaniclal switch under the battery somewhere.
 
The cover doesn't cause overheating. I don't see why everyone thinks this.
well, look at the construction of the Mavic. you have air intake right behind the gimbal. If you put hinders in front of those, air will just not flow as designed. You may have also heart that the Mavic has a cooling fan.

But anyway, fly with it if you like, not my Mavic, not my pictures :)
 
well, look at the construction of the Mavic. you have air intake right behind the gimbal. If you put hinders in front of those, air will just not flow as designed. You may have also heart that the Mavic has a cooling fan.

But anyway, fly with it if you like, not my Mavic, not my pictures :)
It's because of the fan that the cover doesn't cause overheating. Because the cover has a slit and is not completely sealed in the sides, the air intake is still able to suck in the needed amount of air to keep the unit cool, not to mention the massive heatsink on the bottom.
 
  • Like
Reactions: gumaco
This is not the first Drone that DJI makes and it seems obvious to me that a locking mechanism should be designed so that it does not allow flying with a loose battery. Anything else would be unsafe and bad product design.

You can’t turn on a microwave with the door open, right! So why should you be able to fly a drone with an unlocked battery?

When users start flying around with Velcro straps abound the body of a $1000 drone just to hold it together during normal use, then I would have to say it has gone too far. :)

I don't know if the locking mechanism has changed on the new batteries that are colored slightly different from the Mavic, but the original batteries latched down just fine. I understand your point but keep in mind the Mavic is built to a price. Adding latch detection etc would just drive up the price and in the end it's really not needed since most of these problems have been due to the pilots not clicking the batteries properly into place.

Rob
 
It's because of the fan that the cover doesn't cause overheating. Because the cover has a slit and is not completely sealed in the sides, the air intake is still able to suck in the needed amount of air to keep the unit cool, not to mention the massive heatsink on the bottom.


Cyberpower you need to run the mavic on a table for 30 minutes while taking video. Feel the Camera itself, it's kind of surprising how hot it gets. That little slit on the dome is not wide big enough to let in enough air. It has been proven in videos that the Mavic is a few degrees hotter with the dome is on vs off. Unfortunately the guy did not measure the Camera. I suspect that is an even bigger issue.

Rob
 
Last edited:
Cyberpower you need to run the mavic on a table for 30 minutes while taking video. Feel the Camera itself, it's kind of surprising how hot it gets. That little slit on the dome are not wide big enough to let in enough air. It has been proven in videos that the Mavic is a few degrees hotter with the dome on vs off. Unfortunately the guy did not measure the Camera. I suspect that is an even bigger issue.

Rob
I am not familiar with such videos.
 
I am not familiar with such videos.

I will try to locate one tomorrow. Basically the guy does a hover test with and without the dome and measures the temp of the heatsink with a laser thermometer. It's not a huge difference but it was cold out so as you know sucking in 60 deg air versus 98deg air will magnify his results.

Rob
 
In response to the point made about battery installation being user error, I'd like to reiterate that I have 2 batteries (one which was original with the drone) which seat and click perfectly. The third battery (one of two in the fly more pack) appears to click in and seat just like the other two, but actually requites significant force to fully engage the clips and is then under pressure, which leads to the possibility of the battery unseating during flight.

Had I been more experienced at flying the Mavic, I may have picked this up. However, this is a manufacturing issue which needs to be addressed.

In other news, I opened a case with DJI on 10/04. So far, customer services has been very poor. They sent the shipping label to the wrong email address, communications turnaround takes a minimum of 48 hours, the drone was held by UPS, in Belgium of 5 days, and although they’ve now had it for 3, they have not started working on it, yet. I made a mistake by dealing direct with DJI and should have taken it back to the shop I bought it from as I would have had a replacement in 2 days. DJI really needs to get its act together.
 
I will try to locate one tomorrow. Basically the guy does a hover test with and without the dome and measures the temp of the heatsink with a laser thermometer. It's not a huge difference but it was cold out so as you know sucking in 60 deg air versus 98deg air will magnify his results.

Rob

I think it was done by Drone Valley...
 
What he is saying for those not familiar with the 176_36 or DAT files is that when we look at the record of the flight we do not see any information being recorded as to how much CURRENT (Amps) is being used by the Mavics motors or any of its systems. This also means that we have no power reading from the individual Mavics motors. The Data is just blank!

I think Budwalker is being cautious because we have never seen this before and we do not know why it has happened. Last night I looked at several other logs and they all had power info but this one was unique.

WHAT DOES IT ALL MEAN?

Well it means that either something was broken in the DJI software and it just stopped recording the data. That could also mean the the CPU had no idea how much power was being drawn by each motor and that could have triggered a shutdown in mid air.

It could also mean that the Data was being monitored and recorded but not stored in the right places for DATCON to pick them up.

It could also just be a recording issue caused by some kind of firmware glitch and it had no bearing on the crash whatsoever. IMHO it's a little too coincidental that we find this odd log info in a Mavic with a properly latched battery that just shut off in Mid Air and crashed. As Budwalker said this is definitely a case of a defective Mavic and it seems to be a one off incident that is most likely caused by something going wrong with the firmware when it was updated by the DJI software.

Rob

Rob, can you tell me what the corresponding field "176_36" would be in CsvView? I'm happy to take a look at some of the other .dat files that users with similar issues have posted.
 
Rob, can you tell me what the corresponding field "176_36" would be in CsvView? I'm happy to take a look at some of the other .dat files that users with similar issues have posted.
176_136 is a record type particular to the Mavic. It contains totalVolts, current, batteryTemp(C), volt1, volt2, and volt3. There are other signals that DatCon then computes from these such as Watts, minCurrent, etc. If the .DAT is missing the 176_136 records then none of these fields will have values. AFAIK .DAT files that don't have 176_136 records are extremely rare. I'd be interested in knowing about examples other than that discovered here.

You may be looking at other AC types. E.g., CsvView/Datcon doesn't know about battery info in the Inspire2 (I was actually working on that this morning).
 
176_136 is a record type particular to the Mavic. It contains totalVolts, current, batteryTemp(C), volt1, volt2, and volt3. There are other signals that DatCon then computes from these such as Watts, minCurrent, etc. If the .DAT is missing the 176_136 records then none of these fields will have values. AFAIK .DAT files that don't have 176_136 records are extremely rare. I'd be interested in knowing about examples other than that discovered here.

You may be looking at other AC types. E.g., CsvView/Datcon doesn't know about battery info in the Inspire2 (I was actually working on that this morning).
Thanks for that clarification. I haven't looked at any files, yet. I wanted to know what to look for so that I could take a look at a couple other files from downed Mavics. I had tagged you and Rob in an earlier post inviting you to look at one on the DJI forums. I figured you both were too busy to have a look :)
 
176_136 is a record type particular to the Mavic. It contains totalVolts, current, batteryTemp(C), volt1, volt2, and volt3. There are other signals that DatCon then computes from these such as Watts, minCurrent, etc. If the .DAT is missing the 176_136 records then none of these fields will have values. AFAIK .DAT files that don't have 176_136 records are extremely rare. I'd be interested in knowing about examples other than that discovered here.

You may be looking at other AC types. E.g., CsvView/Datcon doesn't know about battery info in the Inspire2 (I was actually working on that this morning).

Ok, so this might be interesting... I just had a quick look at a .dat file from one of the other threads I was talking about. In at least one of the files (FLY025) the fields you mentioned were blank, as well as a bunch of other fields that presumably also rely on 176_136.

Here's the thread: My Mavic Pro crashed! After updating the Firmware

and the .dat files: https://kmjj0x.s.cld.pt/

I'm not actually sure which of the files corresponds to the flight in which the Mavic fell. I think your analysis would definitely be quicker and more thorough than mine from here on :)
 
  • Like
Reactions: DanielDuarte
Lycus Tech Mavic Air 3 Case

DJI Drone Deals

New Threads

Forum statistics

Threads
130,585
Messages
1,554,117
Members
159,590
Latest member
Philip Chura