On Tuesday 22 August 2006, at 15:39 (Moscow Time), a Tu-154 airliner of Saint Petersburg-based Pulkovo Airlines sent an SOS signal and disappeared from radar contact. There were thunderstorms in the vicinity of the flight, and the aircraft entered an area of severe turbulence, during which its angle of attack increased to 46 degrees and its forward airspeed dropped to zero. It entered a deep stall from which the crew could not recover. It crashed north-west of Donetsk, near the village of Sukha Balka.