An investigation into the cause of a fatal plane crash near the Western village of St. Mary's will rely heavily on information learned from survivors.
National Transportation Safety Board spokesperson Clint Johnson said that is because the Cessna 208 Caravan was not equipped with a cockpit voice recorder or a flight data recorder.
"That makes the survivor interviews extremely important," Johnson said.
Garrette Moses, 30, is among six survivors of the Western Alaska crash on Nov. 29 that left four people dead.
In an interview with KTUU, Moses described thick fog in the moments leading up to the moment when the airplane abruptly fell from the sky.
"I was wondering how come it was getting so thick," Moses said of the fog. "The pilot would constantly check on the outside of the plane, and I noticed it was getting pretty iced up."
Pauline Johnson, another survivor, also told KTUU that weather conditions deteriorated shortly before the crash.
"We were diverted to Saint Mary's because of the thick fog that we were having," Johnson said, which prompted the flight pattern to change.
Federal reports show that Cessna 208 Caravans have a bad track record: they sometimes become coated with ice during flights, which negates efforts to de-ice before takeoff and causes all types of problems that are not common for other passenger planes.
The NTSB in a 2011 report detailed 47 fatalities from accidents involving Cessna 208 Caravans that were covered with ice.
This NTSB photo shows rough ice on the front edge of a wing of a Cessna 208 Caravan, not the one that crashed in Western Alaska.
15 of 26 accidents leading to fatalities highlighted in the report were covered with ice accumulated in-flight.
In addition to interviewing survivors, Johnson said a Washington-based meteorologist will be consulted by NTSB investigators, including a planned visit to Alaska once the wreckage from the plane is moved to an NTSB facility in Anchorage.
Investigators have already completed the on-site portion of their investigation, Johnson said, and the plane will soon be relocated from the hillside where it wrecked.
That should happen within a couple weeks, but a final report will take much longer.
"We should have this wrapped up in nine months to a year, at the most, but again to stress we are at the very formative stages of the investigation," Johnson said.