Close Call Today

[Hillbilly1236]

Took the Mini2 for a short flight from the house towards the mountain behind us and got up to 240m elevation (I know it's over 120 but it was only about 20m above the tree tops). I noticed the drone flight indicator was showing the drone wobbling side to side and I thought it must be windy so I hit the RTH and as it was flying back I was constantly lowering it to maintain a reasonable elevation above the tree tops. Then I noticed a message across the bottom of the screen that said "motors overloading land drone". I recall reading a thread here somewhere and that message appeared when the props were icing up. So I cancelled the RTH and stopped the drone to check out a landing spot and the message went away. I then flew it back and all was well. I think I dodged a bullet today.

I was using my iPad Air and doubt I would have seen the message if I was using my phone. Funny thing is I have flown in a lot colder weather without incident. Today was 5C and I've flown in -15C. There were a few clouds today but they were way above my flight altitude. Whole thing seems odd but I'm glad I seen the message and didn't panic (this time).

 

[slup]

... the props were icing up. ...Funny thing is I have flown in a lot colder weather without incident. Today was 5C and I've flown in -15C...

It's not the cold alone that cause prop icing ... if the dew point is near the actual ambient temp (where you fly) ... & it's below freezing, then you risk prop icing.

So perhaps it was a lower temp up there at height & the dew point was right there also ...

 

[eaglesurfing]

That is going to be a problem again.
I am sure we will see some more post about it because moisture is returning.

 

[Deleted member 103366]

Re 240m, I think you will find that the legal ceiling relates to the height above the ground DIRECTLY BENEATH the drone and NOT the height relative to the take off point.
You either have some 220m tall trees that are missing from the Guinness Book of Records or the ground covered by the trees climbs significantly and you may well have been legal, check your local terrain maps.

Re the warnings, try replaying the log of the flight from/in the flight records section of the "me" or "profile" section at the front of the App

 

[Rich QR]

It's not the cold alone that cause prop icing ... if the dew point is near the actual ambient temp (where you fly) ... & it's below freezing, then you risk prop icing.

So perhaps it was a lower temp up there at height & the dew point was right there also ...

One further point: the actual ambient temperature doesn't even have to be below freezing. When the pressure of air is increased, its temperature increases, and when the pressure is reduced, temperature falls. As air flows over the props, the pressure will increase in some places and drop in others. Air flowing over the upper surface of the prop will generally be a bit below ambient pressure and temperature, so you can sometimes get icing when ambient temperature is a degree or two above freezing.

Of course, there's also the issue that temperature generally decreases with altitude, so the drone may be colder than your thermometer. And your thermometer may be off by a bit, as well.

Any way you look at it, visible moisture and near-freezing temperatures are a combination to beware of.

 

[Hillbilly1236]

Re 240m, I think you will find that the legal ceiling relates to the height above the ground DIRECTLY BENEATH the drone and NOT the height relative to the take off point.
You either have some 220m tall trees that are missing from the Guinness Book of Records or the ground covered by the trees climbs significantly and you may well have been legal, check your local terrain maps.

Re the warnings, try replaying the log of the flight from/in the flight records section of the "me" or "profile" section at the front of the App

I replayed the flight log but all I see is a plan view of the flight path and 2 altitude warnings that showed up when I reached the 120M max alt I had set in the flight controls and the second one when I exceeded the 120m above the take off area. There were no messages about the motor overload showing up. Is there somewhere else this information is located?

The drone was always considerably less than 120 m above the ground. As I noted earlier I kept the drone about 15 to 20 m above the trees, probably less. I was chasing the side of the mountain behind us.

 

[Deleted member 103366]

The warnings are probably in the txt flight log but with the Mini2 that log is, I believe, encrypted and the normal tool used here, CsvView, can not read it.
I think airdata can read some or all of it but the output is appreciably less detailed than what was available from CsvView.
To access the logs follow the instructions on DJI Flight Log Viewer | Phantom Help

 

[GFields]

You may get the same message if the drone is fighting against the wind.

 

[Hillbilly1236]

You may get the same message if the drone is fighting against the wind.

Good point. That would explain why the message went away when I stopped it but there was no wind where I was and the drone was on a downward tack back towards me. Guess there is no way to know for sure but I think it was more likely an icing up situation.

 

[Hillbilly1236]

I finally got around to uploading my flight info to the "DJI Flight Log Viewer" but for some reason it would read the TXT file. So I set up an account with Airdata and it worked fine there. However the flight information for the above flight only showed 2 warnings and they were the 2 altitude ones. There was no warning recorded about the motor overloads.

Should I be concerned that this showed up on the bottom of my screen but was not recorded in the flight data? If this thing crashed and there was no record of why, would the warranty cover it?

 

[slup]

I finally got around to uploading my flight info to the "DJI Flight Log Viewer" but for some reason it would read the TXT file. So I set up an account with Airdata and it worked fine there. However the flight information for the above flight only showed 2 warnings and they were the 2 altitude ones. There was no warning recorded about the motor overloads.

Should I be concerned that this showed up on the bottom of my screen but was not recorded in the flight data? If this thing crashed and there was no record of why, would the warranty cover it?

The Airdata presentation of the log just scratches on the surface of all info that's in the .TXT log ... in order to see everything other tools need to be used that require more understanding of what the data actually is & what it indicate.

Furthermore it's usually 2 more logs besides the .TXT that can be used, they show all raw sensor & motor data ... the craft .DAT & the mobile device .DAT log

The craft .DAT have been encrypted for all drone models after Mavic Pro 1 ... so those no one besides DJI can read. The mobile device .DAT & the mobile device .TXT have been readable for all ... until lately that said.

Since the launch of the MM2 the mobile device .DAT have also been encrypted & unreadable ... only DJI can. Then from DJI FLY app v1.2.2 also the mobile device .TXT have got a new encryption ... which only Airdata in some way have been able to decrypt ... but they are the only ones that can, for time being at least.

Even if you can't see, or Airdata doesn't show the messages... DJI can, if they really was issued.

 

[Hillbilly1236]

The Airdata presentation of the log just scratches on the surface of all info that's in the .TXT log ... in order to see everything other tools need to be used that require more understanding of what the data actually is & what it indicate.

Furthermore it's usually 2 more logs besides the .TXT that can be used, they show all raw sensor & motor data ... the craft .DAT & the mobile device .DAT log

The craft .DAT have been encrypted for all drone models after Mavic Pro 1 ... so those no one besides DJI can read. The mobile device .DAT & the mobile device .TXT have been readable for all ... until lately that said.

Since the launch of the MM2 the mobile device .DAT have also been encrypted & unreadable ... only DJI can. Then from DJI FLY app v1.2.2 also the mobile device .TXT have got a new encryption ... which only Airdata in some way have been able to decrypt ... but they are the only ones that can, for time being at least.

Even if you can't see, or Airdata doesn't show the messages... DJI can, if they really was issued.

Thanks for that info.

Seems like I am on a journey of ever changing rules, regulations and restrictions. If I could only keep up.