Russian aviation investigators on Tuesday suggested pilot error likely caused the crash of a passenger jet from Moscow that killed all 50 people on board on the weekend.
The Tatarstan Airlines flight plummeted into the ground and burst into flames while trying to land at Kazan airport 720 kilometres (450 miles) east of Moscow late Sunday.
Video footage showing shocking images of the Boeing 737 plane on its fatal nosedive.
"Judging from the preliminary information from the black box, the nose-dive of the plane and the crash could be the consequence of incorrect actions by the crew in an abnormal situation," a source close to the investigation told the Interfax news agency.
The crash happened after the pilots decided not to land at the first attempt and instead turned around, for reasons yet to explained, and crashed on the second attempt to land.
A statement by the Interstate Aviation Commission which is investigating the accident had earlier appeared to put the blame on pilot error rather than a technical fault, although without specifically saying so.
It said that the crew had failed to perform a "standard landing procedure in accordance with established norms".
"After reaching 700 metres (altitude) the plane went into an intense nosedive which at the end of flight was at an angle of 90 degrees," it said. "The plane hit the ground at great speed -- more than 450 kilometres (280 miles) an hour."
It said there were no signs indicating engine or system failure.
Video footage of the disaster taken by security cameras at the airport shows the plane hurtling towards the ground and then exploding in a blinding flash of light.
The footage, published by the lifenews.ru website known for its contacts with the security forces, shows how a cloud of flame erupts above the crash site and then lifts to reveal almost no immediately visible wreckage of the plane.
Forty-four passengers and six crew lost their lives in the crash.
The disaster claimed the lives of Irek Minnikhanov, the son of the leader of the Tatarstan region, Rustam Minnikhanov, and the head of Russia's FSB security service in Tatarstan, Alexander Antonov.
Also among the dead was a Briton, Donna Carolina Bull, 53, and a Ukrainian national, Margarita Oshurkova, the emergencies ministry said. The rest of the victims are all believed to be Russian citizens.
The Boeing 737 plane owned by Tatarstan Airlines, the regional carrier of the Tatarstan region in central Russia, was 23 years old and had had seven different owners during its life. It had undergone repairs after a hard landing in Brazil in 2001.
by Ben PERRY © 2013 AFP
Date: Nov 19, 2013