Motor shut down in cold weather??

[dss123]

Hey guys...

First post as I'm very disappointed by the support I have got from DJI support on this one.

Flying my new Mavic Air before Christmas. A cold morning with some mist, but by no means baltic.

Got some great early morning footage over the Peak District - lovely frosty sunrise. Full 20 minute flight with no issues.

An hour back in the warm indoors, drone and fresh battery both at room temp. Took outside for another quick flight. Probably a few degrees warmer than the first flight....

2-3 minutes in got a warning..... "Motor current warning - fly with caution", followed seconds later by complete loss of power to all four motors. Crash, broken prop, scratches, but otherwise a very lucky escape as the drone was not too high, overhead and landed on grass.

DJI support tell me that motor shutdown is a "protection feature" when the air temp is too cold!! Seems crazy!! They have since deleted their tweet that says it's a protection feature!

Shutting off the motors while it's flying doesn't seem a good way to protect a drone to me!

None the less, they say this is a flight environment issue so won't repair the drone under warranty.


Anybody else had motors spontantiously switch off in normal UK winter weather? What sort of temps have people flown in?


The Mavic Air website has all sorts of breathtaking images of snowy, icy, frozen landscapes, which, from what DJI are saying would represent inappropriate / unsafe flying conditions.


Really worried about flying in the cold now.

 

[HiYa]

Wow, that was bad support and service from DJI!!!
I've seen youtube videos where they have been flying in -20 and -35 celcius with no problem.
Have been flying in -5 with no problems with Mavic Pro.

 

[go-ahead-doubledown]

As I reside in a very cold climate, it's either fly in low temps or keep it in the case. I fly about 3-4 days a week, usually well below freezing.. Have never had an issue. Battery time is slightly reduced, but nothing significant. How bad was the "mist"? I would suspect moisture may have had a role.
If motors are still not functional, I would try placing the AC in a bag of rice. Can't hurt to try.

 

[dss123]

As I reside in a very cold climate, it's either fly in low temps or keep it in the case. I fly about 3-4 days a week, usually well below freezing.. Have never had an issue. Battery time is slightly reduced, but nothing significant. How bad was the "mist"? I would suspect moisture may have had a role.
If motors are still not functional, I would try placing the AC in a bag of rice. Can't hurt to try.

Thanks mate - very interesting. I am also thinking that the fog / mist played a role in this.

Luckily the drone is working fine... I'd just like to work out why it happened because if it was cold enough to kill the motors on this particular occasion, that will really limit my flying in the UK winter.

Convinced drone thought it was nearer the ground maybe or fog just messed with temp sensor?

 

[go-ahead-doubledown]

Couple photos of frozen fog, taken last month.

 

[BearSwartz]

Given the conditions you talked about, if it was below freezing I'd say you iced your props. Ice buildup would quickly cause a drastic motor overload situation forcing a shutdown. Do you know what the temp and dew point were that morning?

 

[Kilrah]

The guy who tweeted had no idea of what he was saying, it's BS.

If you were in fog and it was below freezing your props likely got coated in ice, requiring increasingly high power from the motors until they get to full speed and that still isn't enough.

 

[tcope]

Motors don't turn off in cold weather, the battery does. The DJI Go app will give you a warning when the temp of the battery low and it will limit power. At lower temps the battery won't turn on but it also won't just turn off if already on.

 

[zocalo]

Given the conditions you talked about, if it was below freezing I'd say you iced your props. Ice buildup would quickly cause a drastic motor overload situation forcing a shutdown. Do you know what the temp and dew point were that morning?

That's one likely cause, and the most critical bit with it is the bit about the dew point, but this seems a little less likely given that plenty of people fly in sub-zero temperatures with no problems other than reduced battery life - I've done this myself and been down to 10-15min from a full battery. The difference is usually that there isn't an excess of moisture in the air at higher latitudes/altitudes as it's precipitated to the ground and got stuck there in the form of snow and ice. If you fly through fog or mist (e.g. a good indication of being the wrong site of dew point), then you are going to pick up water vapour on the drone, which will then get into the works, and if the temperature falls too then it'll turn into ice as well.

Another option would be the battery had an issue and turned itself off to protect itself from damage, they are supplying the current after all - which is what the error message was warning about. If I had to guess, I'd say the battery picked up some moisture from the first flight, which caused a battery problem with the second, resulting in the available current falling below what was required for motor operation. Best practice (unless you want to roll the dice for some dramatic footage) is to stick to clear air and avoid mist/fog/clouds, and if the AC has residual moisture on it after a flight make sure it's had plenty of time for everything to dry out, possibly assisted by silica gel bags (or rice at pinch).

 

[dss123]

Thanks for the replies all.....

I think DJI Support are fobbing me off.

It wasn't that cold. The UK has not really had any cold temps so far this winter.

When I collected the drone and the bits that broke off after the crash, they all looked "normal" to me. Not particularly cold to the touch and certainly no ice evident.

It had only been in the air a few minutes and hadn't really gone anywhere (lucky for me).


I'm sure the fog I ascended through caused some sort of sensor failure.... But DJI won't admit that, they'll just say the motors froze up and then they haven't got to fix under warranty.

Complete nonsense

 

[RayOZ]

Can you post flight logs? It'd be interesting to see what error message and warnings it had before shutdown. Did they actually say motor shutdown as a protection feature? Sounds more like ice build-up and motor seized, or current draw was too large and it shut down.
I think it's the sudden change in environmental conditions, perhaps from warm to cold that caused icing. A bit like fogging on your glasses.
I can't really see it as warranty issue. There was no software or hardware defect. If a plane crashes due to icing on the wings, can the airline ask the manufacturer to replace it under warranty?

 

[Canuk]

If the battery temp was too cold you can have problems. I live in northern Alberta so I know all about freaking cold . I launch and then bring up the battery temp while at hover . Temp must be over 15c before the bird goes off flying . I had a cold battery once and things were not going well . It sat too long in the cold before starting the motors and cooled off . A warm battery has power . A cold battery is a dud that don’t want to make the needed amperage

 

[Kilrah]

Current aircraft firmware doesn't let you take off with a battery that's too cold.

When I collected the drone and the bits that broke off after the crash, they all looked "normal" to me. Not particularly cold to the touch and certainly no ice evident.

Ice usually cracks away on a crash, and also melts quick if it isn't actually freezing at ground level.

I'm sure the fog I ascended through caused some sort of sensor failure.

Again many people fly in fog and in super cold temps without issue. Just not both at the same time.

With a Mavic air when you fly in fog you want to disable the bottom sensors too or you might have trouble descending. Never heard of that shutting down motors unexpectedly though.

 

[dss123]

Can you post flight logs? It'd be interesting to see what error message and warnings it had before shutdown. Did they actually say motor shutdown as a protection feature? Sounds more like ice build-up and motor seized, or current draw was too large and it shut down.
I think it's the sudden change in environmental conditions, perhaps from warm to cold that caused icing. A bit like fogging on your glasses.
I can't really see it as warranty issue. There was no software or hardware defect. If a plane crashes due to icing on the wings, can the airline ask the manufacturer to replace it under warranty?

I'm afraid I don't have the flight logs as, to add complication, I changed my phone and lost my most recent back-up, so lost my GO 4 App and flight logs.

My issue is that I didn't feel the conditions were outside what would be considered safe to fly and I had flown safely earlier that day when is was colder.

I just don't like being fobbed off, saying it was too cold too fly and the motors froze. Particularly when DJI themselves have pictures on their website taken in obviously freezing conditions?? And I hear plenty of stories about people flying in much colder temps?

If there is something inherently dangerous about flying in fog + cold, I think it's very important to warn users about that .

 

[dss123]

Can you post flight logs? It'd be interesting to see what error message and warnings it had before shutdown. Did they actually say motor shutdown as a protection feature? Sounds more like ice build-up and motor seized, or current draw was too large and it shut down.
I think it's the sudden change in environmental conditions, perhaps from warm to cold that caused icing. A bit like fogging on your glasses.
I can't really see it as warranty issue. There was no software or hardware defect. If a plane crashes due to icing on the wings, can the airline ask the manufacturer to replace it under warranty?

Yup - "low environment temp which triggers protection mechanism"... they later deleted the tweet.

 

[RayOZ]

There’s no black and white answer. Different conditions will lead to different outcomes. DJI do have guides available about operating in cold environments. E.g. Battery Care. There are a couple of sections about cold weather. You probably could find guide for the AC as well.

 

[dss123]

There’s no black and white answer. Different conditions will lead to different outcomes. DJI do have guides available about operating in cold environments. E.g. Battery Care. There are a couple of sections about cold weather. You probably could find guide for the AC as well.

Odd that they should say battery should be used above minus 10 degrees. There's no way it was as cold as that when my drone crashed.

Yet the instructions for the drone say only fly above zero degrees.

I suppose you live and learn.

Flying in fine warm clear weather for me from now on.

 

[RayOZ]

Yup - "low environment temp which triggers protection mechanism"... they later deleted the tweet.

View attachment 58474

Ok. I don’t think you can assume one person’s answer reflect the definitive answer. I am an engineer and countless times I’ve encountered technicians from manufacturers that have no idea how their own product works. Problems with their product, contact their support tech, got going down the wrong rabbit hole to troubleshoot.
I was thinking abt this protection mechanism you mentioned earlier. I think maybe the protection mechanism is for the motor overload, not the cold weather. It’s either shut off all motors and let the AC free fall, or continue to operate until one or motor overloads and it falls spinning unpredictability and uncontrollably. Either way, AC is going down, and perhaps shutting off all motors at once was the safer option.
Without flight logs, we won’t know what caused the motor to shutdown. It’s all speculation now.
Sorry to hear it happened anyway.

 

[JDawg]

Hey guys...

First post as I'm very disappointed by the support I have got from DJI support on this one.

Flying my new Mavic Air before Christmas. A cold morning with some mist, but by no means baltic.

Got some great early morning footage over the Peak District - lovely frosty sunrise. Full 20 minute flight with no issues.

An hour back in the warm indoors, drone and fresh battery both at room temp. Took outside for another quick flight. Probably a few degrees warmer than the first flight....

2-3 minutes in got a warning..... "Motor current warning - fly with caution", followed seconds later by complete loss of power to all four motors. Crash, broken prop, scratches, but otherwise a very lucky escape as the drone was not too high, overhead and landed on grass.

DJI support tell me that motor shutdown is a "protection feature" when the air temp is too cold!! Seems crazy!! They have since deleted their tweet that says it's a protection feature!

Shutting off the motors while it's flying doesn't seem a good way to protect a drone to me!

None the less, they say this is a flight environment issue so won't repair the drone under warranty.


Anybody else had motors spontantiously switch off in normal UK winter weather? What sort of temps have people flown in?


The Mavic Air website has all sorts of breathtaking images of snowy, icy, frozen landscapes, which, from what DJI are saying would represent inappropriate / unsafe flying conditions.


Really worried about flying in the cold now.

I don't see where you actually say what the temps were you were flying in? Could you post your flight log? DJI Flight Log Viewer | Phantom Help

Edit- I see you do not have your flight logs and with that all is specualtion, cold may not have had anythng to do with it. I have seen many posts where people are flying in single digit weather.

 

[dss123]

I don't see where you actually say what the temps were you were flying in? Could you post your flight log? DJI Flight Log Viewer | Phantom Help

I'm afraid I don't have the flight logs. I can only recall the temp being "cold". Above freezing though. It's not been that cold in the UK this winter.

I think the fog must have played it's part. Could have been colder at higher altitude I guess?


DJI do have some winter tips on their website. They talk about cold batteries, reduced run times etc. But nowhere do they warn specifically about the dangers of fog and the potential for motors to just spontaneously switch off!