SIAI S.58

In 1924, the Regia Marina (Italian Royal Navy) issued a requirement for a replacement for its Macchi M.7ter flying boat fighter.

SIAI proposed an armament of two fixed, forward-firing 7.7-millimeter (0.303-inch) Vickers machine guns mounted on the hull on either side of the cockpit.

[1] The S.58 made its first flight early in the summer of 1924 and on 25 August 1924 set a world altitude record for aircraft of its type by reaching 5,831 meters (19,130 feet) with a payload of 250 kilograms (551 pounds).

SIAI built three prototypes, but the Regia Marina opted to save money by re-engining the Macchi M.7ter to extend its service life rather than purchase a new aircraft.

SIAI did, however, build at least one more S.58, which the Scuola di Alta Velocità (High Speed School) at Desenzano used.