Hoping some of the more experienced pilots here can chime in:
What's a safe distance to fly from potential sources of magnetic interference, power distribution lines, large metal structures, cell towers, etc. The manual recommends avoiding flying near these but doesn't really define what "near" is.

Been flying / building drones for a few years and had a pretty epic flyaway with DJI Naza flight controller on a 550 sized quad (luckily I have understanding neighbors and know some good roofers). I'm nearly sure it was pilot error, rushing to get a test flight before a storm and nightfall, and not paying attention to the flashing bootup lights.

Recently got the Spark Flymore (iPhone 6s / OTG) and I'm determined to minimize my risk of anything similar happening again. Tell me if this is overkill but I've read the manuals twice. I have a printed pre-flight checklist, check compass and GPS readings within the Go4 app before takeoff, have an EMF/magnetometer app, check KP readings on www.uavforecast.com, hover at least the first 30-60 seconds, and fly with 4 or 5 GPS bars. I don't calibrate the compass unless prompted to by the app, but I might consider it if I travel more than 1,000 miles away. Is there anything else I'm missing? I want to all but eliminate the chance of a flyaway. Appreciate the wisom folks.  

Ernie

You can enter the wifi setting and check the signal of channel. Please note that magnetic interference can have a bad effect on image transmission and it can cause disconnection. I would recommend you fly in a place with good signal and choose the best channel before flight.

Not sure, if that "near" always is so easy to put in meters!

But more important, I think, is anyway to try to prevent the Spark from picking up interferences just before take of.
And there is isn't meters but cm, methinks!

Meaning ANY object, in reach, that can have some steal or iron inside, or creating a 'field' around itself, should be avoided.

DJI Elektra Posted at 2017-11-28 23:30
You can enter the wifi setting and check the signal of channel. Please note that magnetic interference can have a bad effect on image transmission and it can cause disconnection. I would recommend you fly in a place with good signal and choose the best channel before flight.

Thank you for the reply. To clarify, the signal readings of the channel in the WIFI settings are for the RC to the Spark, or for the phone to the RC or they share a channel? Though I realize OTG cables aren't officially supported, when using it I no longer see the signal strengths in the WIFI settings.

Also, do you have any thoughts on proper distances away from metal structures?  

Thank you!

S-e-ven Posted at 2017-11-28 23:51
Not sure, if that "near" always is so easy to put in meters!

But more important, I think, is anyway to try to prevent the Spark from picking up interferences just before take of.

Very helpful, thank you! So if I understand you, being "near" to metal structures is most crucial during takeoff and landing but not as much during flight.

*wisom = wisdom... and ironic misspelling.

ernie_halter Posted at 2017-11-29 00:52
Very helpful, thank you! So if I understand you, being "near" to metal structures is most crucial during takeoff and landing but not as much during flight.

Probably both is important.
But only one thing you can 100% prevent from happening.
And it seems, that a little compass problem in the beginning can become a bigger one during flight.
In case you have a concrete bench somewhere, or something like that, just place your powered on Spark on to it.
And see the warning showing up. Lifting it 10 cm , the warning goes away.

This might help

https://forum.dji.com/forum.php? ... &fromuid=260008

ernie_halter Posted at 2017-11-28 23:59
Thank you for the reply. To clarify, the signal readings of the channel in the WIFI settings are for the RC to the Spark, or for the phone to the RC or they share a channel? Though I realize OTG cables aren't officially supported, when using it I no longer see the signal strengths in the WIFI settings.

Also, do you have any thoughts on proper distances away from metal structures?  

Please note that if the channel in the app show 5.8G, it represent the channel between RC and AC is 5.8 G. I would not recommend you use OTG cable.
For a better flight performance, please take the signal sign showed in your app as reference.

DJI Elektra Posted at 2017-11-29 02:55
Please note that if the channel in the app show 5.8G, it represent the channel between RC and AC is 5.8 G. I would not recommend you use OTG cable.
For a better flight performance, please take the signal sign showed in your app as reference.

So looking at the signal strength indicators I see that blue is my currently selected channel. Aside from checking that there isn't a bunch of interference (big red lines all over the place) on nearby channels, is it important to note how tall my blue line is, and is it preferred to see it taller or shorter?

Last question, why are OTG cables not recommended?

Thank you again for answering so many questions. Just want to learn as much as I can.

Cheers!

ernie_halter Posted at 2017-11-29 23:01
So looking at the signal strength indicators I see that blue is my currently selected channel. Aside from checking that there isn't a bunch of interference (big red lines all over the place) on nearby channels, is it important to note how tall my blue line is, and is it preferred to see it taller or shorter?

Last question, why are OTG cables not recommended?

Ernie, if most of the channels are green, it means that the signal is strong. I would recommend you choose the strongest signal to fly your spark. Please note that the tallest one will experience the strongest interference. OTG is not fully tested. Thanks for your cooperation.