A wedding flyover that turned tragic. A plane that mysteriously veered off course and slammed into a mountain. A pilot who survived a crash only to succumb to the raging currents of an icy waterway. These are just a few of roughly 125 air disasters that occurred in Alaska in 2015 and challenged one of the busiest branches of the National Transportation Safety Board. Go inside this remote regional office during six air accident investigations, and follow examiners as they attempt to determine the probable cause of each crash, be it man, machine, or environment.