Letov Š-50The Letov Š-50 was a 1930s prototype Czechoslovak military general-purpose monoplane, designed and built by Letov.DevelopmentThe Š-50 was an all-metal twin-engined low mid-wing monoplane that first flew in 1938. It was powered by two 420 hp Avia Rk.17 radial engines. It had a fixed landing gear and twin fins and rudders. Following the German occupation, development was stopped.