Went for our long distance flight attempt today, flew a test flight with a 6S 2600mAh LiPo and then put in the 18650 batteries in, the log unfortunately shows both flights as I forgot to reconnect so I have calculated the time and total distance from the launch of the second flight to the landing.
Basically we did a 300m diameter Loiter for most of the flight, biggest problem was the phugoid motion of the plane losing height on every downwind leg and having to regain the lost height on the upwind leg using precious amps to do so. I tried just about every parameter to tune the plane better throughout the first hour but could never get it to behave.
Special thanks to the devs (especially Tridge and Paul Riseborough), to Steve B. for assisting and UAVDS for making it possible
Plane: Super Sky Surfer
Motor: Maytech MTO3548 790Kv
Prop: APC-E 9x6
Batteries: 6S4P NCR18650b 25.2V, 13600mAh
Battery weight: 1172g
AutoPilot: APM2.5, APM:Plane v2.78.
Weather: Calm (0-4km/h), clear blue sky, 26°C. Altitude: 1668m ASL
Time flown: 126m 53s
Total Distance flown: 116.475km
Calculated consumption on nominal capacity: 115mAh per km (will update after recharge).
Estimated current draw: 5.2A average
Lowest voltage on pack 18.0V
Average speed: 55km/h
Tlog: https://db.tt/UfVPiyBE (12MB)
KMZ: https://db.tt/1Tmzim1W (3MB)