The pilots of a Boeing 737 that plunged to earth at the Kazan airport, killing all 50 aboard, lost speed in a steep climb then overcompensated and sent the plane into a near-vertical dive, according to a preliminary report released Tuesday by Russian aviation experts.
The Moscow-based Interstate Aviation Committee, which oversees civil flights in much of the former Soviet Union, said the plane's engines and other systems were working fine until the moment the plane hit the ground Sunday night.
The Tatarstan Airlines plane was coming from Moscow into the central city of Kazan, 720 kilometers to the east. The Russian aviation experts said the plane's two pilots had failed to make a proper landing approach on their first attempt and then began a second run.
They put the plane's engines on maximum power, raising the plane's nose up at a sharp angle, causing a quick loss of speed.
At an altitude of about 700 meters, the crew then tried to gain speed by taking the plane into a dive but it hit the ground at a near-vertical angle in a spectacular crash.
The climb and the subsequent plunge lasted only about one minute and the plane struck the ground at about 450 kilometres per hour, the report said.
The report drew its conclusions from data retrieved from one of the plane's two onboard black box recorders. A commission statement said the voice-recording tape that captures the crew's conversations had not been found, even though its container had been recovered.
Such "loss of control" accidents are responsible for more deaths than any other type of plane crash because they are rarely survivable, according to the Flight Safety Foundation, an industry-supported global aviation safety nonprofit based in Alexandria, Virginia.
The head of Tartarstan Airlines, Aksan Giniyatullin, told a news conference Tuesday in Kazan that the two pilots had plenty of flying experience ranging from 1,900 to 2,500 hours and had undergone all the necessary instruction. However, he said the crew apparently had no experience with attempting a second landing.
He also said the plane had undergone regularly scheduled maintenance on Nov. 15 two days before the crash.
Tartarstan Airlines records showed that the plane was built 23 years ago and had been used by seven other carriers prior to being picked up by them in 2008. The company has insisted that the aircraft was in good condition.
The plane did suffer a loss of cabin pressure in November 2012, Giniyatullin told reporters, but could not specify the cause of that failure, according to the RIA-Novosti news agency.
In 2001, the plane was damaged in a landing accident in Brazil that injured no one.
The carrier has had a good safety record but appears to have run into financial problems recently. Its personnel went on strike in September over back wages, and the Kazan airport authority has gone to arbitration to claim what it said was Tatarstan Airlines' debt for servicing its planes.
Flight safety is a problem in Russia. Industry experts have blamed some recent Russian crashes on a cost-cutting mentality that neglects safety in the chase for profits. Insufficient pilot training and lax government controls over the industry have also been cited as factors affecting safety.