Now that this thread has mellowed, for anyone returning to this thread,
I'd like to add some additional independent technical commentary. I have no dog in this fight, but do admit to a deep respect for this amazing photographic & aviation technology! The intent is not to argue or dispute or win or lose. Simply to comment with another opinion - I downloaded FlyinB's Flight Data Recorder FLY163.DAT file from Dropbox after he posted the link and independently analyzed it. The opinions stated here are my own, based on the data in the log files and nothing more than just another opinion… This is the aircraft DAT file log, not the mobile device .TXT log submitted to Healthy Drones.
The flight data file matches the flight FlyinB submitted to Healthy Drones dtd March 25th @ 6:58 PM for a flight of only 1 minute and 14 seconds. According to the Aircraft Flight Data recorder log, the Aircraft was under power for 5 minutes and 43.7 seconds. It was inflight only 1 minute and 18 seconds (78400 msec). Healthy Drones analyzes the mobile device .TXT log and you will see that the aircraft .DAT log agrees with the data in the .TXT log. This flight appears, perhaps, to be a continuation flight after FLY162, which was the longer 15 minute flight across the highway and return. Despite the discussion that this was a single flight, the log shows a specific motor start, takeoff, and flight for only 1 minute and 18.4 seconds. The short flight, FLY163, took off, climbed to about 8 meters and was commanded into a hotpoint (POI) mission, climbing to 43 meters. This flight began with only 23.99469763% battery level, triggered a low battery RTH at 14.273 volts and then appears to have fought between the RTH command and the mission. The battery functioned completely within normal parameters throughout the flight and crash. At 44 secs of battery power, a CSC commanded the motors to start. The aircraft took off at 46 secs of power and slowly climbed to about 8 meters.
On the aircraft side, the flight controller receives aileron, elevator, throttle, and rudder values. FlyinB’s startup CSC looks like this in the log file. A max stick deflection is -10000 for left/down and 10000 for right /up. A neutral stick is 0.
Startup_CSC
At about 39.5 secs into the flight, the aircraft began climbing to 43.3 meters and started the POI around the house. At 1 minute and 11.5 secs of flight, the battery (5630 [Ctrl<11>] REQ_BATTERY NAVI_GO_HOME ctrl_navi_go_home) invoked a low battery RTH at 14.273 volts. The RTH triggered a climb to the RTH altitude of 50 meters and the aircraft turned to head home, but something (probably Litchi) tried to turn the aircraft back to the mission path. It appears that the programs fought for control for about 7 seconds and the commanded stick combinations resulted in a CSC at 1 minute 18.4 seconds or 78400 msecs. (5976 [M. Stop]REQ_RC_NORMAL|5976 Motor Start 1 Total 78.48|5976 CTRL reset all by motor stopped | 5976 [ACT.msg] ACT_GO_HOME motor stopped!)
The log shows that the commanded stick movements for a CSC started at 1 minute 17.9 seconds and continued until the motors stopped at 1 minute 18.4 seconds.
<------- CSC
Lessons Learned: Pilots must maintain situational awareness by maintaining control of their aircraft, scanning the GO App for battery levels, alert messages, and take controlling actions when necessary. I believe that running both the GO App and Litchi contributed to this crash. I think taking off with only 23.9% battery also contributed to this accident. If Bryan says that he never touched the controls, then likely the two programs were fighting for control and flew the aircraft into autonomous CSC stick commands. Regardless, the motors shutdown because of a commanded CSC.
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