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.

The Savoia-Marchetti S.55 was a double-hulled thick-section cantilever monoplane flying boat that was designed to perform both civilian and military operations, dependent upon equipment fitout.

In general terms, its design was largely original and possessed numerous features that increased its practicality as a platform for naval military tasks such as minelaying and torpedo attacks.

[4] On militarised flying boats, the stern of each hull would accommodate a tail gunner from which a relatively favourable range of fire could be obtained.

Mounted on top of the rectangular horizontal stabilizing surface were three triangular vertical fins, the trailing edges of which were outfitted with hinged balanced rudders.

These engines were arranged in tandem within a streamlined nacelle that was mounted high above the centre section of the aircraft, supported by a series of struts.

[9] After flying south to Bolama, at that time in Portuguese Guinea, they hoped to cross the ocean without another stop but were forced down at Cape Verde, reaching Brazil on 23 February 1927.

[citation needed] The Brazilian João Ribeiro de Barros and his crew of three made another crossing in S.55 "Jahú" on 24 April 1927.

Four months later, on 16 June 1927, they arrived back in Italy, having flown nearly 48,280 km (30,000 mi) in 193 flying hours and having made just over 50 stops, including Rio de Janeiro, Buenos Aires and New York City.

[13] 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.

The aircraft, registered I-BAUQ and named "Jahú", was the S.55 used by Commander João Ribeiro de Barros in his crossing of the South Atlantic in 1927.