[1] The new aircraft was displayed to the public for the first time in July 1957; the design was approved for mass production after testing was completed in June 1959.The inefficient use of cabin volume contributed greatly to the low payload/TOW ratio which was much lower than that of the contemporary Ilyushin Il-18, but which was still higher than the Tupolev Tu-104.Following results of flight tests and at least two fatal crashes, an effective tailplane deicing system was retrofitted to all remaining aircraft.[1] A total of 104 aircraft were built, including the prototype and static test airframes, entering service with the Ukrainian Civil Aviation Directorate of Aeroflot from 27 April 1959,[1] proving popular due to large cargo volume (when fitted with reduced seating) and excellent field performance, making the aircraft suitable for use on small undeveloped airfields.[1] On 26 February 1960, at Lviv Danylo Halytskyi International Airport, CCCP-11180 crashed due to reduced longitudinal stability and control authority caused by icing of the tailplane.