Cold weather test

[Bchris]

It was -17 F this morning with a thick vapor cloud over Lake Superior so I thought I would send my Mini 2 up for some shots. I didn't do any flying around, just hovered at 380 feet. After 20 minutes of hovering and waiting for the sun to rise above the cloud I still had 33% battery left. I figure I probably had another 5 minutes of flying time left but decided to play it safe and bring it down. Does extremely cold weather affect battery life? Yes, but not nearly as much as I expected. Also, with DJI Fly 1.2.2 (Android) I was experiencing several communication dropouts per minute. With 1.2.4 I only had one dropout which was before I even took off, so I'm hoping the update at least partially fixed the problem.

Brad

 

[slup]

It was -17 F this morning with a thick vapor cloud
...I didn't do any flying around, just hovered at 380 feet
...Does extremely cold weather affect battery life? Yes, but not nearly as much as I expected.

Just a friendly warning related to cold weather flying ...

First this with prop icing with following motor errors that develops to either a total motor shut down or a forced autolanding ... If the dew point is close to the air temp where you're flying & it's below freezing it's a major risk that ice will start to form around the props, totally destroying their ability to create thrust ... making the motors rev up until they no longer can go faster ... then game over. So seeing fog or mist is a clear sign of that the temp are near the dew point.

Secondly ... flight times for the batteries isn't the only thing that can be affected in cold weather flying... that's the easiest to handle. When the battery is used in colder environments the internal resistance increases ... meaning that with higher amp draw the battery in much more prone for major voltage drops ... if one cell momentarily falls down to 3V it's again game over, DJI drones will then force autoland & you can't do anything to stop it. In general, cold weather usage wear much more on the batteries ... & the damage can accumulate & the disaster show up much later.

My advice is to always follow the recommended operational temp. for your Mini 2 it's 0C - 40C (32F - 104F) ... and when you are flying in colder temps, operate the AC carefully without max stick inputs, this to minimize the amp draw.

 

[Deleted member 103366]

Not arguing but just seeking education.
Once the battery is warmed, by use, why is the temperature of cold surrounding air an issue?
I could see it possibly affecting the outer 'layer' of the 'battery' but judging by my P3 and M2P batteries the outer most layer is warm to the touch after a flight.
Admittedly I have only flown in air down to +3C.

 

[Bchris]

Just a friendly warning related to cold weather flying ...

First this with prop icing with following motor errors that develops to either a total motor shut down or a forced autolanding ... If the dew point is close to the air temp where you're flying & it's below freezing it's a major risk that ice will start to form around the props, totally destroying their ability to create thrust ... making the motors rev up until they no longer can go faster ... then game over. So seeing fog or mist is a clear sign of that the temp are near the dew point.

Secondly ... flight times for the batteries isn't the only thing that can be affected in cold weather flying... that's the easiest to handle. When the battery is used in colder environments the internal resistance increases ... meaning that with higher amp draw the battery in much more prone for major voltage drops ... if one cell momentarily falls down to 3V it's again game over, DJI drones will then force autoland & you can't do anything to stop it. In general, cold weather usage wear much more on the batteries ... & the damage can accumulate & the disaster show up much later.

My advice is to always follow the recommended operational temp. for your Mini 2 it's 0C - 40C (32F - 104F) ... and when you are flying in colder temps, operate the AC carefully without max stick inputs, this to minimize the amp draw.

I appreciate the advice thank you. The humidity was in the mid 30's and the fog/sea smoke was over a mile away over the lake itself.

 

[slup]

Not arguing but just seeking education.
Once the battery is warmed, by use, why is the temperature of cold surrounding air an issue?
I could see it possibly affecting the outer 'layer' of the 'battery' but judging by my P3 and M2P batteries the outer most layer is warm to the touch after a flight.
Admittedly I have only flown in air down to +3C.

It's a completely other thing with -27C (-17F) than with +3C ... the battery will never reach it's optimal working temp, even if slightly warm to touch after the flight that's not the correct temp for massive amp draws necessary for full throttle + full elevator. Ever wondered why batteries drop their volt from 4,2V immediately after take off & then recovers after a couple minutes ... even if the batteries have indoor temps to start with..?

 

[Deleted member 103366]

It's a completely other thing with -27C (-17F) than with +3C ... the battery will never reach it's optimal working temp, even if slightly warm to touch after the flight that's not the correct temp for massive amp draws necessary for full throttle + full elevator. Ever wondered why batteries drop their volt from 4,2V immediately after take off & then recovers after a couple minutes ... even if the batteries have indoor temps to start with..?

Cool .......or may be not lol, thanks.

With regards to " Ever wondered why batteries drop their volt from 4,2V immediately after take off & then recovers after a couple minutes ... even if the batteries have indoor temps to start with..?"
Actually I have never taken notice of that before, guess I will have to look from now on. Thanks

 

[slup]

Cool .......or may be not lol, thanks.

With regards to " Ever wondered why batteries drop their volt from 4,2V immediately after take off & then recovers after a couple minutes ... even if the batteries have indoor temps to start with..?"
Actually I have never taken notice of that before, guess I will have to look from now on. Thanks

Here you have a fresh example from today, a M2 ... some cold weather flying with a battery started at indoor temp. Note how the voltage drops from start ... the pilot periodically pinns both the throttle & the elevator (seen by the Zspeed & the heading speed. This one ended after 37sec with a failure in cell 3 going to 2,52V & a forced autolanding.