I think this is the record for the longest battery only electric RC airplane flight, excluding the use of fuel, solar cells, or slope soaring. I am happy to answer your questions in the comments section. There is more detailed build info here:    • Phoenix 2400 Second Autonomous Endura...  

10 hours and 45 minutes
340 miles or 547km across the ground
Phoenix 2400
Matek F405 Wing with Arduplane code
12x12 APC propeller
Racerstar 4108 600KV motor
Turnigy Plush32 30A ESC (LVC disabled)
50,000 mAh 4s LiIon battery pack that I made with LG M50 cells

Here are my STL files for 3D printing: https://www.thingiverse.com/thing:456...

0:00 Intro
0:51 Assembly
2:06 Arming
3:05 Launch
4:43 Condensed Flight
7:04 Landing
7:54 Touch Down
8:46 Airplane Tour
9:50 Summary