The A.R. (Assalto Radioguidato) flying bomb was also conceived by Sergio Stefanutti, this time in cooperation with engineers Ermenegildo Preti and Stelio Frati. The Italian air arm had previously gained the distinction of being the first in the world to employ a radio-controlled flying bomb operationally, when, on August 13, 1942, it sent a much-modified SM.79 against a part of the British Fleet lying off the Algerian coast. Although unsuccessful, the attempt encouraged General Ferdinando Raffaelli, designer of the radio-control system, to urge the development of a cheap, expendable machine to fulfill the purpose more effectively.
The result was the A.R., a simple wooden mid-wing monoplane powered by a 1000 h.p. FIAT A.80 radial engine. The fuselage was of oval construction with plywood skin, and was to have contained two sealed-in 2200-lb. bombs. Wings and tail surfaces were angular and untapered. No flaps were required as landings were not anticipated. After experiments with take-off trolleys, a simple fixed undercarriage was employed which could be dropped after the bomb was airborne.
Flight tests began in June, 1943. Unlike the reaction-powered German V-weapons, the A.R. required a pilot for take-off. After radio control took over the guidance in flight, he bailed out. With a bomb load of 4400 lb. and a total weight of 13,200 lb., the A.R. was expected to have a maximum speed of 225 m.p.h. with undercarriage jettisoned. Five of the flying bombs were built at the Venegono plant in 1943 but none were ever used. The last four were destroyed .before being tested. Wingspan was 55 ft. 9112 in., length 49 ft. 21/2 in., and wing area 409 sq. ft. The empty weight was 7936 lb.