Photographer unknown. Aircraft prepared for ground tests, possibly related to the underwing gun pods. Note the hydraulic jacks below the fuselage to relief the aircraft weight from the carriage and to keep it perfectly horizontal. Note also the restraints to ground and the amount of test equipment into the rear cockpit bay. The pod is a UNI-POD 0127 by the FFV Maintenance Division swedish company, that was offered to equip light aircrafts, helicopters and jet-trainers.

The S211 lost against the MB339 in a competition for a jet trainer for the Italian air force, it was taken on as a private project by SIAI-Marchetti, hence the civil registration worn.

Third prototype. Later preserved at Museo Storico Piana Delle Orme, Borgo Faiti, Latina, Italy.

3rd prototype S211.