My best guess from the information we currently have. Pilot error, 100%. He had many opportunities to turn back, but didn't. Accidents are a chain of events leading up to the crash, he didn't break the chain.
Best guess, he eventually went IIMC, didn't have the situational awareness to know he was headed straight for the mountain. He did, however, initiate a climb. Now what happened after is the big question... but no matter what happened next, they never should have been in that position to begin with.
Did they clip something like wires, the mountain itself? Possibly. But, from what I've read, the turning descent at 2000fpm and 184mph, would only have me thinking main rotor damage. Tail rotor, no. That would be an immediate auto rotation and controlled descent around the 2000fpm, but at 80 knots, ish, not twice that.
How often did he fly actual IFR? Did he get spacial disorientation and, despite having instruments to reference, simply lose control and all reference with little time to regain control?
I think the only thing we do know is they shouldn't have continued that flight, or not gone in the first place.
RIP to all
This is a most reasonable speculation IMHBO. As for the pilot's poor judgement to fly that day, in light of the weather, Kobe was the host of that tournament, and had probably decided not to drive, and knew that they would be late (2-hour drive) if they did not take the helicopter, so he made the pilot an offer he couldn't refuse. The rest was a chain of bad decisions, as you say.
