MOSCOW, July 31. /TASS/. The investigation of the May 2019 Sukhoi Superjet 100 crash in Moscow’s Sheremetyevo Airport considers a pilot error to be the main cause of the tragedy, a source in the investigative agencies told TASS on Wednesday, underlining that the investigation may take up approximately 18 more moths.

"The investigation of the aviation incident with the Sukhoi Superjet at Sheremetyevo will go on for 12-18 months more," the source said. "It is because a large set of air, aviation and technical tests need to be carried out. However, the conclusion can be confidently drawn now that the incident was caused by a pilot error."