[tonyarkles]

I think if the people you're working with insist on narrowing it down to a single Root Cause, they're missing the entire point of the exercise. I work with large drones day to day and when we do an accident investigation we're always looking for root causes, but there's almost always multiple. I don't think we've ever had a post-accident RCA investigation that resulted in only one corrective action. Several times we have narrowed it down to a single software bug, but to get to the point where a software bug causes a crash, there's always a number of other factors that have to align (e.g. pilot was unfamiliar with the recovery procedure, multiple cascaded failures, etc)