Conversation so far:
What was one of Harrison Ford's incidents?
On October 23, 1999, Harrison Ford was involved in the crash of a Bell 206L4 LongRanger helicopter.
Was Harrison Ford the pilot of the Bell 206L4 LongRanger helicopter crash?
The NTSB accident report states that Harrison Ford was piloting the aircraft over the Lake Piru riverbed near Santa Clarita, California, on a routine training flight.

Question: What was the cause?
Self-contained rewrite: What was the cause of the Bell 206L4 LongRanger helicopter crash with Harrison Ford?