The National Transportation Safety Board says a deadly Alaska State Trooper helicopter crashed last year because the pilot decided to fly into bad weather and the agency lacked adequate safety management.
The trooper pilot, another trooper and an injured snowmobiler they had just rescued died in the March 2013 crash near Talkeetna.
The NTSB released its report Wednesday, saying the pilot's motivation to complete the search-and-rescue mission contributed to the accident. That factor increased the risk and affected his decisions.
The board also says the Alaska Department of Public Safety had a "punitive culture" because its internal investigation of a previous accident involving the pilot focused too narrowly on the pilot instead of addressing underlying safety deficiencies.
A department statement says it has since examined its aviation practices.