Regional governmental authorities in Yaroslavl state that the Yakovlev Yak-42 which crashed on take-off from the city's airport failed to gain height, and clipped a navigation aid before falling to the ground.
The aircraft came down near the Tunoshenka river, 200m (660ft) from where it joins the Volga, losing its empennage on impact while the forward part of the trijet disintegrated.
Yaroslavl's regional division of the Russian internal affairs ministry said the Yak Service aircraft "did not climb after take-off, turned, hit a [beacon] and fell outside the airport".
Just two survivors were found from the 37 passengers and eight crew. One of the survivors was the flight engineer, the other a player from Yaroslavl's Lokomotiv ice hockey team which had been flying to Minsk.
The Yak-42's tail section came to rest submerged in water, and the Interstate Aviation Committee said it is working on lifting this rear structure in order to locate the flight recorders.
Divers and recovery personnel have located the 43 victims of the accident, said the Russian emergency situations ministry.