04/30/2011. Remarks by Johan Visschedijk : "Silvercraft SpA was formed at Milan in early 1962 and Doctor Emilio Bianchi designed a light all-metal three-seat general-purpose helicopter, designated XY it was first flown in October 1963.
It was further developed with financial and technical assistance of shareholder SIAI-Marchetti (36%) into the SH-4, which had some original features such as the semi-rigid rotor and simplified mechanics, with parts which could easily be inspected from the outside and were quick to replace. Five prototypes were built at SIAI-Marchetti's facilities at Sesto Calende between 1965 and 1968, and powered by a 235 hp Franklin 6A-350-D engine the first SH-4 (I-SILX c/n 001) made its maiden flight at Vergiate in March 1965, with Dario Pavan at the controls.
The SH.4 was certificated by the RAI and FAA in September 1968, being the first helicopter of all-Italian design and construction to receive both Italian and U.S. certification. In basic form the SH-4 was suitable for pilot training, utility, survey, police, ambulance, military liaison and observation duties, and as the SH-4/A for agricultural use. The SH-4/C had a supercharged Franklin engine.
With the aid of Fiat Aviazione (Motori), who manufactured mechanical parts for the rotor transmission, a production batch of about 50 SH-4s was started at Sesto Calende. Silvercraft began deliveries in 1970, but the firm ran into difficulties over the Franklin engine, which had gone out of production, and a total of only 21 SH-4s was completed with individual examples being exported to Brazil, South Africa, France and Holland, while one aircraft was delivered to the Italian Air Force. Production ceased 1977.
The pictured third prototype was first flown in early 1967, also registered as I-SILX."