Warplanes of Italy: Regia Aeronautica, Savoia-Marchetti S.55

Savoia-Marchetti S.55 maritime patrol flying boat

(Regia Aeronautica Photo)

The S.55 featured numerous innovative design features. While the passengers and cargo were housed within the twin hulls, the flight crew controlled the aircraft from a cockpit located in the thicker section of the wing between the two hulls. The S.55 had two inline contra-rotating propellers, mounted in tandem. The engines were canted sharply at an upward angle. Two wire-braced booms connected the triple-finned tail structure to the twin hulls and wing.During August 1924, the S.55 performed its maiden flight. Shortly after its introduction, the S.55 set multiple records for speed, payload, altitude and range. Numerous flying boats saw service with the Regia Aeronautica and export operators such as the Spanish Air Force and the Royal Romanian Naval Aviation as reconnaissance bombers and maritime patrol aircraft. While some examples were active by the outbreak of the Second World War, the type only played a marginal role in the conflict due to their age.

The Italian Air Marshal of the time, Italo Balbo, became famous for organizing a squadron of S.55s for Atlantic crossings, culminating in his 1933 flight with 24 aircraft to Chicago's Century of Progress International Exposition. On 1 July 1933, General Balbo commanded a flight of S-55s from Orbetello, Italy, completing the flight in just over 48 hours, maintaining a tight "V" formation. These large fleets of aircraft were sometimes called a "Balbo". Numerous aircraft were introduced by the Regia Aeronautica and served as a long-range bomber and patrol aircraft. By the Second World War, the service's S.55 fleet was no longer considered to be serviceable and the type was only ever held in reserve. (Wikipedia)

Variants
S.55
Prototypes and original production model delivered from 1927 to 1930, 90 built ,including two prototypes.
S.55C
Civil variant delivered from 1925 to 1926, eight built.
S.55P
Improved civil variant with enlarged hull for ten passengers and enclosed cockpits delivered from 1928 to 1932, 23 built.
S.55A
Military variant delivered with 418 kW (560 hp) Fiat A.22R engines, 16 built.
S.55M
Variant with some wood structures replaced by metal, seven built by Piaggio in1930.
S.55 Scafo Allargato
Widened and deepened hull and enclosed cockpits, 16 built by Savoia-Marchettiand 16 built by CANT.
S.55 Scafo Allargatissimo
Variant with greatly enlarged hull, 20 built by Savoia-Marchetti, 16 built by Macchi and six built by CANT.
S.55X
Variant fitted with Isotta Fraschini Asso 750 engines for North Atlantic formation flights, later armed and used as a reconnaissance-bomber. 25 built. (Wikipedia)

(Regia Aeronautica Photos)

Savoia-Marchetti S.55X maritime patrol flying boat.  

Savoia-Marchetti S.55X flying boat of Marshall Italo Balbo Sqn, visiting Victoria, Prince Edward Island in 1933.  (Library and Archives Canada Photo, MIKAN No. 3651011)

(JCMA Photo)

Savoia-Marchetti S.55X maritime patrol flying boat.  The last remaining example is preserved in the TAM "Asas de um sonho" museum, Sao Carlos, Sao Paulo, Brazil.  The aircraft, registered I-BAUQ and named "Jahú", was the S.55 used by Commander Joao Ribeiro de Barros in his crossing of the South Atlantic in 1927.

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