The official report into the crash of a Russian passenger jet over Ukraine last year has concluded that pilot error was to blame.
Russia says ageing Tupolev planes of this type will be phased out
All 170 people on board the Pulkovo Airlines Tupolev 154 were killed after it came down in bad weather in a field near Donetsk last August.
The report said a trainee pilot was at the controls at the time of the accident.
It said the more experienced pilot failed to assist him.
The Russian Interstate Aviation Committee blamed the crash on "a lack of control over flight speed and a failure to carry out instructions on preventing the plane from stalling".
It also said the pilots were inadequately prepared for flying in stormy conditions, and that the training instructions for the plane contained no appropriate guidance for flying in such a scenario.
The plane was flying in bad weather from the Russian resort of Anapa to St Petersburg on 22 August.
Russia's Transport Minister Igor Levitin said the ageing Tu-134 and Tu-154 aeroplanes are to be retired from civilian use over the next five years, according to reports.
Pilot training requirements are also to be increased.
"We will toughen procedures for testing pilots, increasing the number of training hours, especially for co-pilots," he was quoted as saying by RIA-Novosti news agency.
In 2006 there were three major air disasters involving a Russian airline or airport.