By virtue of its RR Viper engine, Aermacchi first displayed their MB.326 at Farnborough as far back as 1966 and it became a regular attendee through till 1978 when the MB.339 started to supersede it. I-AMKK was also at the 1970 and 1972 shows and reappeared in 1976 having been re-registered I-IVAO. It now resides atop a pole at Zagarolo in Italy, coded RS-33