Design and development SIAI S.58

1 design , development

1.1 s.58
1.2 s.58bis
1.3 s.58ter

design , development
s.58

in 1924, regia marina (italian royal navy) issued requirement replacement macchi m.7ter flying boat fighter. compete macchi m.26 production order replacement, siai developed s.58. wooden, single-seat, single-bay biplane hull based on of siai s.51 racing flying boat had participated in 1922 schneider trophy race. s.58 s engine, 221-kilowatt (296-brake horsepower) hispano-suiza hs 42 v8 driving pusher propeller, mounted on struts above hull. siai proposed armament of 2 fixed, forward-firing 7.7-millimeter (0.303-inch) vickers machine guns mounted on hull on either side of cockpit.

the s.58 made first flight in summer of 1924 , on 25 august 1924 set world altitude record aircraft of type reaching 5,831 meters (19,130 feet) payload of 250 kilograms (551 pounds). siai built 3 prototypes, regia marina opted save money re-engining macchi m.7ter extend service life rather purchase new aircraft. siai did, however, build @ least 1 more s.58, scuola di alta velocità (high speed school) @ desenzano used.

s.58bis

siai later fitted first s.58 prototype 313-kilowatt (420-horsepower) fiat a.20 v12, redesignating re-engined aircraft s.58bis. in 1927, regia marina again held contest replacement macchi m.7ter, , siai entered s.58bis. regia marina found impressive enough make plans procure 97 s.58bis aircraft, these plans cancelled when regia marina again chose economy measure extend m.7ter s service life re-engining it, , no production order materialized s.58bis.

s.58ter

in autumn of 1928, s.58ter, modified s.58bis employing fiat 20 v12 engine, flew first time. in 1929, regia marina again organized contest m.7ter replacement, , siai entered s.58ter. s.58ter lost out macchi m.41bis , did not win production order.