We have informed about the accident already sooner in a news. The investigators focused on the fuel intake system to the engines. They have found out, that the pilots after the accident used in incorrect order the fuel cut-off switch and emergency fire levers. The fuel cut-off switch should be controlled by the commander, the emergency fire levers by the first officer to make their operation faster. This model of Boeing 777 did not yet have the protection against the usage in wrong order and thus incorrectly there were firstly used the fire levers, which launch the engine fire extinguishers and cut one wire, which directly connects the engine fuel spar shut-off valves with the levers. These valves are also operated by the second wire through relays, which was accidentally damaged due to the aircraft damage and although the fuel cut-off switch was later put to the closed position, the relays did not operate and kept the valves open. This caused fuel leak at the aircraft drop site and could cause catastrophic results by accidental fire. The fire luckily did not occur.

But the mystery is still the real reason of the accident. The no doubt reason was the insufficient amount of fuel at the high pressure pumps intakes, which causes cavitation at their outlets. But the reason for the low amount of fuel is still a mystery. All filters turned out to be passing through and although the aircraft was flying in a very cold area behind the mountain range of Ural, the thermal sensors did not encounter any dangerous fuel temperature drop under the safe 3 degrees of Celsius above the freezing point of the fuel, which is for the used type Jet A-1 -47 degrees of Celsius. By examining the real sample of fuel from the accident site it turned out, that the real freezing point of the fuel was even -57 degrees of Celsius, which showed that the fuel was of very high quality. The Boeing company follows to try to simulate the exact fuel flow dynamics by the simulation of the exact conditions during the flight. So the investigation is still open even after four months after the accident.