Long fpv flying of Dart250 : Geumosan mountain

This is second and first long fpv flying of Dart 250 . The maiden flying of this Dart 250 was long time and close range flying within 2 kilometers for endurance test. The total flying distance of that flying was about 50 kilometers for 1hours. In this flying, I went to Geomosan mounthain at Gumi. 28:20 At top of Geumosan, I met relative heavy wind passing over the top of mountain After returning to home at top, the tailwind made Dart 250 more speedy and sometimes cause unstable wobble. Although I set 23dB patch antenna in video receiver, the transmitted video at near top of mountain was not so good because relative lower powered video transmitter. specification airplane : Dart 250 of ZOHD AUW : 262gm Servo & motor : PNP default , Sunnysky 1406 kv 2600, 5inch prop. RC receiver : Crossfire nano receiver FPV & recording camera : runcam split 3 nano Video transmitter :TBS Unify Pro32 Nano 5G8 400mw FC : Matek 411 mini c iNav GPS receiver : BN-200 of Beitian Battery : Sanyo Li-ion 18650 3500mah 2S1P