This U.S. Coast Guard image shows the downed plane on Mount Jumbo on Prince of Wales Island.

The National Transportation Safety Board describes poor visibility and a disoriented pilot in the moments prior to a chartered floatplane crashing into the east face of Jumbo Mountain. All 10 passengers were injured — six of them severely — in the 2018 crash.

The NTSB doesn’t pinpoint the cause of the crash. But it delivers a narrative that describes marginal flying conditions, coupled with inadequate safety oversight and critical missteps leading up to the crash.

The pilot — a former Navy aviator who was in his fourth year with the air carrier — was not injured. He told investigators that visibility was reduced to virtually nothing in a matter of seconds and that he briefly mistook snowpack for water in the moments before impact.

The NTSB found institutional problems in oversight and at the airline: the FAA inspector told investigators that the assigned workload was heavy, leaving too little time to complete oversight responsibilities for commercial aircraft.

Investigators also found that Taquan Air’s director of operations had taken a second job in Anchorage — in violation of federal rules — and only visited  Ketchikan about once a month. That’s as the carrier operated about 60 flights a day during the peak summer season. Investigators say the FAA knew Taquan’s director of operations had taken a second job but didn’t believe that was prohibited.

Investigators also heard that Taquan Air aircraft routinely kept a terrain awareness warning system disabled during flights. The systems are designed to set off an alarm if the aircraft comes close to an obstacle and is designed as a failsafe in low visibility conditions. Company pilots told NTSB investigators the system was never activated.

The July 10, 2018 crash involved a de Havilland Otter operated by Taquan Air that was bound for Ketchikan from a fishing lodge on Noyes Island. Less than an hour after takeoff the Coast Guard responded to a report that it had crashed 9 miles east of Hydaburg. The NTSB has yet to issue its findings on the four floatplane crashes in the Ketchikan area this summer.