Heh... it don't take much to scare a horse..
Horse farted and scared itself https://m.youtube.com/watch?v=yAuO3GnjCEM
As a long time owner of both horses and helicopters i've come to the conclusion that they is not to dissimilar. Easy to break, expensive to run, and prone to giving yer a fright from time to time if yer not paying attention.
That chopper in the thread starter video looks to be doing nothing out of the ordinary. Likely either landing into wind or approaching over clear ground. Looking closely at the vid there appears to be open paddock under the final approach line of the chopper.
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