"Does your RTL work? 
Check your compass alignment and calibration. I have seen this exact issue before and it wound up being that.

Also, check your NAV speed limits. Could be too strong."

"Looks like you briefly lost RC connection and probably didn't have a failsafe set. "

"Yup. And Im going to go a step further and say accidental disconnection of battery or PIXHAWK power connection. Current and Voltage are still optimal when it stopped logging. "

"Just came across this thread. To be honest, I have no experience with tower. However, I am a boss at Arducopter and Mission planner.... anyways, there are several ways to accomplish what you want..... What I have done in the past is use a knob on…"

"Autotune?"

"Looks like you might need to mount the pixhawk on a more vibration absorbing material."

"Do you have any throttle curves set on the radio? 

Also setting throttle hover position is important as it seems to be used in a few calculations. "

"If you are using RTL on your failsafe.... I would highly suggest 3.6v per cell. I can tell you with certainty that once lipo cells hit 3.5, they RAPIDLY lose voltage. if you are in a windy environment and in loiter/poshold/auto, then your drone will…"

"Arducopter has default settings built in for the y6. 

Also, just get it able to fly in stabilize and alt-hold, then do autotune. "

"I use LEA-6H and get HDOP down to 1.1 but 1.6 is most common.

Ps. It has NOTHING to do with 3DR. It has everything to do with the antenna, the ublox config, and the location you are in. Also, electronics and motors do mess with GPS. You need to…"

"What did you use for prop adapters?"

"Himodel AX2810-Q 900kv | 8045 | 4s (16.8 max voltage)
NTM Propdrive 2826 1250V | 8045 | 4s (16.8 max voltage)"

"Not joking. What would cause smoking? You mention "decent setup". Can you be more specific? I have a properly rated discharge lipo, an ESC with enough amperage rating for the draw, and a motor."