Savoia-Marchetti SM.80

Savoia-Marchetti

Industry	Aircraft manufacturing
Founded	1915
Headquarters	Italy

The Savoia-Marchetti SM.80 is an Italian-designed amphibious monoplane from the early 1930s, featuring seating for two and a single tractor engine positioned above the wing. Its four-seat counterpart, the SM.80bis, is equipped with a pair of pusher engines.

Design and development

The SM.80 was configured as a cantilever high-wing monoplane. Both the wing and tail surfaces, including the fin and tailplane, were constructed from wood and covered with fabric. The wing structure was divided into sealed compartments to ensure buoyancy should the hull become flooded. The wing tips had a rounded shape, matched by a broad, rounded fin and a tailplane mounted slightly above the fuselage and supported by bracing underneath. Control surfaces—differential ailerons, split elevators, and a rounded rudder—were framed with steel tubing and covered in fabric.

Its fuselage featured flat sides and a stepped underside composed of double planking with copper rivets to resist corrosion, tapering towards the rear. The side-by-side cockpit was set slightly into the wing’s leading edge, while space for baggage or an optional third seat was located near the trailing edge. Stability on water was maintained by fixed flat-bottomed floats attached at mid-span on both wings via pairs of parallel struts. The amphibious landing gear earned attention for its streamlined design: main wheels were enclosed within fairings that rotated approximately 180 degrees rearward before moving upward beside the fuselage, allowing the wheels to retract neatly into the wing roots.

Initially, the first SM.80 was powered by a 112 kW (150 hp) six-cylinder inline Alfa-Romeo Colombo S.63 engine, mounted centrally above the wing on two forward-leaning N-shaped struts complemented by a transverse V-shaped brace. These struts were made from chrome-molybdenum steel tubing and covered with alloy fairings to prevent corrosion. This arrangement positioned the engine ahead of the wing’s leading edge and placed the two-blade propeller well in front of the pilot’s windshield. This version participated in the Egyptian Air Rally in December 1933.

Another variant of the SM.80 flew with a 112 kW (150 hp) CNA C.VI six-cylinder inline engine. The third example, registered in 1934 as a four-seater named SM.80bis, featured a more significant redesign with twin 56 kW (75 hp) seven-cylinder Pobjoy R radial engines in pusher configuration mounted further aft above the wings on either side of the fuselage using similar mountings to the original single-engine model. The cabin was shifted approximately 950 mm (2 ft) forward compared to its predecessor; otherwise, both models shared structural similarities. The SM.80bis weighed about 80 kg (175 lb) more and exhibited reduced maximum speed by roughly 16 mph, although climb performance remained comparable. This speed reduction is attributed to increased drag caused by the twin-engine setup despite both variants having equivalent total power output.

Operational history

Aside from its journey to Egypt in late 1933, detailed records of the SM.80 models' operations are limited. A notable incident involved a fatal crash on 14 July 1935, which claimed the life of Eduardo Agnelli, heir to Fiat and chairman of Juventas. This accident occurred with the first SM.80, an aircraft owned by Giovanni Agnelli, founder of Fiat and Eduardo’s father. It appears that as Eduardo was about to exit the plane, it struck a floating obstruction, causing him to be thrown forward into the propeller. Access to the cockpit on the SM.80 was typically achieved through separate forward-folding windscreens for both pilot and passenger.

The SM.80bis model survived the Second World War and was re-registered before resuming flight operations afterward.

Variants

SM.80

Equipped with a single 6-cylinder inline engine, either the Colombo S.63 or CNA C.VI, configured in a tractor layout. Seating capacity ranged from two to three occupants.

SM.80bis

Featured a twin pusher arrangement powered by a Pobjoy R 7-cylinder radial engine, accommodating four seats.

Aircraft on display

The SM.80bis with construction number 3, initially registered as I-TATI prior to World War II and later as I-ELIO, was exhibited as a static display at the Gianni Caproni Museum of Aeronautics. It has since been relocated to the Parco Museo del Volo Volandia in Vizzola Ticino.