https://en.wikipedia.org/wiki/2024_Haneda_Airport_runway_collision

Resolves once the investigation by the Japan Transport Safety Board is finished, potentially waiting for more information to come out if there's some other investigation ongoing.

"At fault" refers to whichever party violated the procedures they should have been following in a way that caused the collision. If multiple parties violated procedure, I'll resolve to all of them in approximate proportion to the severity and causal impact of their violation. If there were extenuating circumstances for the violation where no reasonable person could have been expected to do better, that violation is ignored.

If nobody violated procedures and it was the procedures themselves that were significantly flawed, resolves to "the procedures". If it's none of the above, resolves to "somebody else/nobody".

For example, if this were about the Tenerife airport disaster, it would resolve to 95% the KLM plane pilots and 5% the air traffic controllers.