The airplane was used as small transport and as a trainer. The fuselage is square with rounded tips and a tall tail fin. Several rectangular windows run along either side of the fuselage. Elliptical wings with square tips are set in the middle of the fuselage. Engines are housed in round fairings high on the rear fuselage, between the wings and the tail plane.
Tail plane is swept and is set at the base of the fin.
Retractable landing gear with nose wheel is very short. Development of 1121 began in 1961. First prototype flew in 1964. The airplane is built by Rockwell in the United States and by IAI in Israel. 1121 is also exported to Canada, Germany, Mexico, and Panama.