(Reuters) - An Alaska commuter airline routinely failed to inform pilots of shifting weather conditions and other hazards leading up to a 2013 crash in western Alaska that killed four people, the National Transportation Safety Board said on Friday.
The Cessna 208B, a single-engine turboprop, had been heading from Bethel to Mountain Village in deteriorating winter weather and crashed about a mile (1.6 km) southeast of St. Mary's Airport in southwestern Alaska. The pilot and three passengers were killed, and six passengers survived with serious injuries.
Prior to the crash, Hageland Aviation Services Inc had failed to follow its own risk assessment plan, and on the day the plane went down the flight coordinators on duty had not been trained properly in those procedures, according to NTSB crash investigation documents released on Thursday.
"The hardest thing is to get this company to police itself," Dale Hansen, a Federal Aviation Administration manager in Anchorage, told NTSB investigators. "If we're not there to watch them, you know, we're not really sure half the time if they're doing it right."
The airline, operated at the time as Era Alaska, which is now called Ravn Alaska, also failed to routinely inform pilots of weather conditions and other possible hazards, the preliminary report found.
Last year, the NTSB urged the FAA to audit several Alaska-based air carriers after a series of accidents over 19 months in which six people were killed.
After the November accident, the companies took action to try to reduce the risk of crashes, the NTSB said previously.
At the time of the crash, Hageland was operating 56 airplanes, employing about 130 pilots, and running 12 bases located throughout Alaska, the NTSB said.
The FAA also needed more inspectors for proper oversight of the fast-growing Hageland, which changed its name to Ravn Connect after the accident. It is among a network of commuter airlines in Alaska.
Clint Johnson, spokesman for the NTSB, said the FAA has substantially "stepped up its oversight of Hageland Aviation" and that the airline has made positive changes, such as installing a new operational control center in Palmer.
Ravn Connect did not immediately respond to a request for comment.
(Reporting by Eric M. Johnson in Seattle; Editing by Victoria Cavaliere, Cynthia Johnston and Lisa Shumaker)