Can hang glider hover straight into wind and keep same position? Isnt resultant force allways  pointing slighlty backward at every wing,so why hang glider is not push downwind by the wind?
From theory that cant be possible,so does wind somehow coming at him at angle from below? ground seems flat,maybe slightly angled..
(Is it easy what his doing or that can do only very very skilled pilots?)
Can he penetrate continusly forward into wind direction in zag-zag motion,first straigt up and then down-forward or maybe with dynamic soaring like birds do?
The ground is not flat, and indeed slightly angled. This is enough to &quot;hover&quot;.
Specifically, the ground slope should be equal or more than the max L/D ratio of the hang glider at the current wind speed. The wind should go 'up' as much as the glider goes 'down' per unit of distance. The ground seems to go up about 2m over a distance of maybe 10m, which is a slope of one in five. An L/D of 5 seems perfectly reasonable for a hang glider.