Determining reason for mid-flight RC disconnect

[tvon]

So I had my first disconnect this weekend, probably my 14th flight. Very nerve racking but it kicked into RTH and came back safely. My spark is at firmware v01.00.0701, using the RC w/ OTG cable to my Android. The phone was not in airplane mode. I had about 16-17 sats connected and no connection warnings previous. In fact i've never gotten even a temporary disconnect error on previous flights. The AC was 100ft up and about 75 feet away. In line of sight, in a field next to a river and roadway. This was a new flight area so my theory is some sort of interference or i've read bluetooth? I'm just trying to figure out what the cause is.. there was no obvious interference like big buildings or powerlines nearby. Below is my flight log, is there anything to be found in there to help determine the reason? Disconnect happens about 5mins in:

DJI Flight Log Viewer - PhantomHelp.com

 

[DesertWindAero]

So I had my first disconnect this weekend, probably my 14th flight. Very nerve racking but it kicked into RTH and came back safely. My spark is at firmware v01.00.0701, using the RC w/ OTG cable to my Android. The phone was not in airplane mode. I had about 16-17 sats connected and no connection warnings previous. In fact i've never gotten even a temporary disconnect error on previous flights. The AC was 100ft up and about 75 feet away. In line of sight, in a field next to a river and roadway. This was a new flight area so my theory is some sort of interference or i've read bluetooth? I'm just trying to figure out what the cause is.. there was no obvious interference like big buildings or powerlines nearby. Below is my flight log, is there anything to be found in there to help determine the reason? Disconnect happens about 5mins in:

DJI Flight Log Viewer - PhantomHelp.com

I reviewed at HealthyDrones.com (Now, airdata.com)

From J to K, you have "Very Poor" signal strength and a bunch of other issues. Possibly a lot of interference since you're in Class B airspace.

Click the link to review on airdata.com (here)

 

[tvon]

Thank you for showing me that. I had not seen that site before, so thank you. Around "J" is where the disconnect happened, so no surprises there. As you see, it went from green to purple very fast.

About the Class B warning- i've never seen this before until after i got the AC on the ground and looked at my flight record. Why would i not get that warning until I got to point J? Is part of the field not in the restricted zone? I've also flown in nearby areas with no issues or Class B warnings.

 

[Eljay]

Looks to me like you're just barely into the class B circle. Moving west just a bit would get you out of it.

 

[tvon]

I'm still unclear about what that means. I understand what the FAA calls a class B, but still unclear what it means to UAV pilots. I was well clear of the airport. Would that cause my AC to disconnect?

Edit: found this thread. (Flying in class B airspace as a recreational pilot) KBOS calls class B 8miles around Logan. I was def within that 8 miles and I didnt notify. However, never got any class B msg until the disconnect... hmmmm

 

[AeroMirage]

I have had this happen plenty of times. It was the app crashing. I still had control of the bird but would have to cancel RTH and restart the app. It wsas real bad for awhile right before the last FW update and I haven't had it happen once since.

 

[Eljay]

I'm not really sure what the UAV rules are, but when I was taking flying lessons man, class B was like STAY AWAY territory.

 

[tvon]

I'm not really sure what the UAV rules are, but when I was taking flying lessons man, class B was like STAY AWAY territory.

As disucussed in the thread i linked above, i was outside of the 5 mile Class B range, but in BOS, its extended to 8mi. So thats the confusion.

Anyway.. I didnt mean to spur FAA rule discussion.. just trying to figure out why my AC got disconnected.

 

[tvon]

Update - Had some successful flights and no disconnects. Since then, I have been flying with my Android phone in airplane mode. Still at a loss for why the sudden disconnect during this instance. Even from google earth view I do not see any obvious magnetic interference sources.