A hard landing can cause a boom strike as can a narrow set of in flight conditions, none of which make it a go to theory as an initiator for this incident. I don't need to wait for a certified gov report before I start to familiarize myself with publically available information and I hope...
The yaw isn't so much a loss of tail rotor function, it's that when the drive train seizes, the inertia of the lifting blades instantly spins the aircraft in the opposite direction with sufficient force that the tail rotor can't counter even if it were still functional.
My animated gifs are here (long) and here (short slo-mo) They are an interesting study in video editing. The source video is not continuous. The file size is controlled by algorithms leaving out "redundant" frames and substituting duplicates (or many more) of other frames to make up the lost...
The tail rotor shaft sits atop the tail structure, enclosed in its own shroud. The two inner members I believe are vertical and horizontal stabilizer linkages. I think they were just pinched as the tail snapped off.
I don't see any torsional component to the tail failure. It looks like a clean break to the right and slightly down, given the break line along the row of rivets. I don't know if a driveline seizure could whip the aircraft around so fast that the tail couldn't follow but that's what it seems...
I don't think so. The videos clearly show the assembly twirling down intact. I believe the blades broke on impact though I could be corrected.
It continually amazes me the penchant for popular knowledge regardless of its senselessness. We already have a clear photo of the self-destructed...
How the turbine held on, by a few threads via the combustion chamber. We can see this in a similar orientation in the crash video (frame grabs posted above).
From a New Zealand report here, a typical powerplant layout.
Also, from the first photo, it appears that the mast is significantly bent.
I noticed from the crash video that the entire drive bay was empty, leaving mostly just the passenger compartment. Posted are four cropped frames (not all...
The tail assembly appears to become unstable as the aircraft starts yawing (or what appears to be yawing). Given the unknown compression parameters applied to the original video, it's difficult to assess what may be algorithm induced artifacts.
Edit: The aircraft might have already rolled...
It appears the aircraft experienced directional stability issues which caused the tail assembly to separate and subsequently the rotor assembly. Note the original video is not continuous.
From New York Times (paywall on some devices)
From the many photos available on the web, the lighting system for the show on the evening of the collapse was standard fare. I've come to believe that lighting and sound equipment is much lighter than in the 60's/70's but the building wasn't...
The rooftop and streetside infrastructure have been significantly upgraded since Google Street View canvased the area in January 2019 (or even August 2019, here). Note the new roof mounted transformer (225KVA from CBC here) and adjacent sidewalk utility pole (from metro.co.uk)
