LA Auto  

I'm guessing the reason the man flared so high is he saw the rooftop of the big warehouse in front of him and either thought he was going to make it there or he just mistook it for the ground (i.e., tunnel vision due to stress). That's the only reason I can think that he'd have used up all the collective so high above the ground (since he clearly committed to doing an autorotational entry at the beginning based on the ADS-B data). The ENG camera video shows he's not below the building roof before the low rotor goes fully steady and the rate of descent speeds up. The security camera footage shows all rotor speed is gone by the last 60-80 feet. Why else would he use all remaining collective so high?