 The first La-250A prototype was finally rolled out on 16 June 1956.Test flights of the five prototypes were plagued by crashes caused by failures of the hydraulic boost system and landing gear as well as poor forward visibility (the latter was corrected with fitting of a new slightly "drooped" nose).La-250A made a single test flight in 1956, only 6 flights in 1957, and a mere 14 flights in 1958.