In total, the fire, which started July 27, ended up burning 459,123 acres and destroying 280 structures.
Over the past few months, investigators have interviewed numerous firefighters who worked on the Mendocino Complex fire.
Their report suggests that tension among leaders, along with substantial communication issues, including radio "dead spots" where communication wasn't possible, might have contributed to the chaos that ensued Aug. 19.
The Cal Fire and U.S. Forest Service "rivalry was evident on this fire, and I believe it was a detriment to the operational tempo and production," one firefighter told investigators.
Additionally, command staff needed more firefighters, including hotshot crews, but couldn't get them because of other large wildfires burning across the state, including the Carr, Cranston and Ferguson fires, the report notes.
L.A. City Fire declined to comment, deferring to Cal Fire. Cal Fire also declined to comment, with a spokesman saying the agency, which helped compile the report, did not yet have a final copy of it.
Ann Carlson, Mendocino National Forest supervisor, said communication is critically important during a large wildfire, and as California will continue to have large wildfires, agencies at every level must find ways to effectively work together, including through training together before disaster strikes.
The Mendocino Complex fire had the potential to burn many homes in the communities surrounding Clear Lake, which was a priority for fire leaders, she said. The fire was regularly burning at least 17,000 acres per day, about 27 square miles.
"It could have been much worse than it was," Carlson said. "Because the resources were focused on those populated areas, we weren't able to put as may resources on the unpopulated part, which is the forest ground, and so that's why it was really actively burning there."
The near-fatal accident that August day was preceded by substantial leadership issues among the fire's command staffs.