Looks like the tail rotor hit something first, if you look at one of the frames you see some foliage gett chopped behind the helicopter thus loss of yaw control you then hear the blades hit the tree canopy. However not sure if this was the result rather than the cause. The sound quality is not great but the rotor sounds very slow and the engine beat not fast / loud enough. Mind you I am only going by a c model ( 3500 hours on them)l only have 50 or so hours on b's and cb's if they were flying one of these so could be the rigt sound. Difficult to get low rpm in a C model as the correlator is pretty effective uo 25" not very good in a b model though