The navigator of a Russian plane that crashed, killing 47 people, had been drinking alcohol, investigators say.
The passenger aircraft, a RusAir flight from Moscow, hit a motorway minutes before it was to land at Petrozavodsk airport in June.
The navigator had drunk enough alcohol before take-off to make him inattentive as he was instructing the pilot to land, investigators said.
But bad weather was also one of several factors in the crash, they said.
The accident at Petrozavodsk, in north-west Russia near Finland, occurred in heavy fog with the crew unable to see the runway's ground lights, the Interstate Aviation Committee report said.
However, the crew did not decide to turn away and make another attempt at landing, and the aircraft hit nearby trees before crashing.
Experts believe the navigator, who was killed in the crash, had consumed the equivalent of a glass of vodka, and that he showed "excessive activity", giving orders to the pilot to speed up the landing.
They also said communication among the crew was poor with the pilot obeying orders unquestioningly and the co-pilot effectively sidelined.
The crash investigators confirmed the plane had no technical problems, and that the crash was the result of errors by the pilot and other members of the crew.
Forty-four people died at the scene of the crash, while three died later in hospital. Five people survived.
The report's findings come as an investigation continues into the crash of a plane carrying a top ice hockey team earlier this month, the latest in a string of air disasters in Russia.