The Interstate Aviation Committee said Tuesday that the reason for Sunday's plane crash in Kazan was faulty maneuvers by crew members, resulting in a loss of speed at low altitude.
A statement on the aviation watchdog's website said the engines and other systems were working properly at the time of the crash, but the plane lost speed when the pilots raised the nose of the plane up at a sharp angle during the second landing attempt. When they tried to remedy the situation by steering the plane downward again, it fell into a nosedive, crashing and killing all 50 people on board.
A mere 45 seconds passed from the moment the second landing attempt began and the crash occurred, and it took 20 seconds for the plane to nosedive, the statement said.
Experts will continue to examine other factors in the crash, including the training given to airline personnel and pilots, and in-flight documentation.
Complicating matters, the black box recovered at the scene was found to be empty.
The general director of Tatarstan Airlines, Askan Giniyatullin, said at a news conference that the pilots of the Boeing 737-500 that crashed upon landing at the Kazan airport had never performed a second landing attempt in flight, the BBC Russian service reported.
Giniyatullin's comments seem at odds with the pilots' extensive résumés. Pilots Rustem Salikhov and Viktor Gutsul had a combined 44 years of in-flight experience, and had fulfilled all necessary preparation to maneuver an aircraft.
Giniyatullin said the company had never had any complaints about the pilots.
He said the flight from Moscow to Kazan had originally meant to use a different type of aircraft, a Bombardier CRJ 200, but plans changed at the last minute "in connection with passenger load."
The Bombardier CRJ 200 ended up flying to Sochi instead, with 40 passengers on board, he said.
Families of the victims will receive financial compensation for their loss after the identification of the bodies is completed, Farid Mukhametshin, head of the state council of Tatarstan, said Tuesday.
The process will take about one month, according to the Tatarstan health department.
Russian authorities and Tatarstan Airlines' insurance company will compensate the victims' families up to 2 million rubles ($61,500) each.