Aeroflot Flight 4225 was a Tupolev Tu-154B-2 that was a domestic scheduled passenger flight from Alma-Ata Airport (now Almaty) in Soviet Kazakhstan to Simferopol Airport in Soviet Ukraine on July 8, 1980. The aircraft reached an altitude of no more than 500 feet when the airspeed suddenly dropped because of thermal currents it encountered during the climb out, causing the airplane to stall before traveling 5 km (3.1 mi) away, crash and catch fire, killing all 156 passengers and 10 crew on board. To date, it retains the highest death toll of any aviation accident in Kazakhstan.