The dive bomber SM.85 was a fairly advanced aircraft for its time. Single-seat twin-engine monoplane with retractable landing gear and fully enclosed cockpit. The fuselage of the aircraft, for the unusual shape of which the aircraft was nicknamed "banana", was designed in such a way as to minimize drag while giving the pilot the best view. The cockpit was heavily moved forward, in addition, to improve visibility, there was a glazed cutout in the floor. The fuselage was made of wood and covered with plywood skin.
Three-spar wing with plywood toe and linen sheathing. Flaps were used instead of brake grilles during the dive.
The tail unit is made of wood, covered with plywood sheathing and reinforced with struts.
The chassis was retracted by turning back into the engine nacelles, the harvesting mechanism is equipped with a hydraulic drive. The tail crutch is equipped with rubber shock absorbers. Due to the weakness of the landing gear, landing with bombs on the aircraft is not provided.
Armament. The bomb bay could hold one bomb of 500 or 800 kg, or two bombs of 250 kg each. One 7.7 machine gun in the fuselage was more symbolic than real armament.
The first flight of the prototype on December 19, 1936. However, according to the test results, it was necessary to reduce the number of originally ordered aircraft.
Due to the weak thrust-to-weight ratio, the rate of climb of the aircraft was less than 2m/s. When the flaps were used as aerodynamic brakes, when they were extended to 90 °, the behavior of the dive bomber in the air became unpredictable. With poor controllability in a dive, a tendency to longitudinal oscillations and a protracted exit from the peak, it was extremely difficult to carry out accurate bombing.
The instability of the dive trajectory, a sharp change in speed and too long exit from the dive also posed a serious danger during anti-aircraft fire.
Serial bombers were distinguished by the 500-horsepower P.VII RC35 engines, improved combined flaps and "reinforced" small arms, which consisted of two bow 7.7-mm machine guns or one 12.7-mm machine gun.
A total of 34 aircraft were built.