The YA1 Cropmaster was an Australian single or two-seater agricultural monoplane produced in two models, first flown in 1964. The YA1 Cropmaster was a low-wing cantilever monoplane powered by either a Rolls-Royce/Continental IO-470-R six-cylinder horizontally-opposed air-cooled engine providing a top speed of 245 kmh (YA1 Cropmaster 250R) or a Rolls-Royce/Continental IO-520 six-cylinder horizontally-opposed air-cooled engine providing a top speed of 253 kmh (YA1 Cropmaster 285). Both versions of the YA1 Cropmaster had an endurance of three hours flying time in normal agricultural use. Research YA1 Cropmaster
 
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