a year ago I posted about the maiden flight of Stephen's concept design for a long endurance hexa. It was fun building it and it was a reliable system with flight times of up to 35 min.
However, since then a lot of things changed - first of all a colleague of mine crashed the hexa into a tree...
Repairing it meant building it again almost from scratch. This was one of the reasons why I started designing my own copter. The other reasons were: I was aiming at even longer flight times and at a copter where you can easily and quickly detach and change the arms/motors for transport as well as to select a specific setup for different payloads. Unfortunately, these aims are usually mutually exclusive.
After several revisions, endless tests, and fighting hard- and software bugs I just started testing the latest and most probably the final version.
Two things: i) I haven't used the optimal motor/prop combination for that payload (I'm waiting for other props) and ii) the final battery voltage was 14.3V (in flight) - although the battery capacity was down to 20% and fail save was engaged. So there seems to be some potential for even longer endurance.
I'll make further tests within the next two weeks and report the results as well as more details.
Thanks again to Stephen for his help!
I updated the images and screenshots and attached the *.gpx file of a new flight with other motors and a reduced payload (Elph 110 instead of S 110). Basically, there is no difference in flight time. But because the voltage was again still around 14.4 V when the 20% capacity battery failsafe was engaged I switched back to loiter. I let it run down a little further.
Conclusion: i) the first motor/prop combination is more effective and I have to wait for new props to arrive, ii) I have to investigate the voltage vs. capacity "issue" (with my other batteries 20% corresponds pretty good to 13.8V), iii) it was in the air for 50min, and iv) these flight times are reproducible.
50 min are possible with one S110 as well.
With two S110 (430g) the flight time is 47min. I switched to RTL at 14.3V and 15% battery capacity left. With 20% battery capacity left the flight time is 45min.