In the early 1970’s it became clear that there was a demand for a medium twin-engine turbine helicopter for the offshore and corporate market. Sikorsky, among others, launched a series of design studies that resulted in a decision to launch the S 76 in 1975. The design that resulted and the decision to proceed with production made it Sikorsky’s first helicopter made from scratch for the civilian market, without major components based on a military design. The other major innovation was that it represented Sikorsky’s first extensive application of composites for the dynamic system and the fuselage. The original version of this helicopter was the S 76A. This was superseded by the S 76A Mark II in 1982 and modification kits were made available for all earlier S 76 A. This helicopter was originally referred to as the S 76 Spirit. This marketing name did not catch on and the helicopter is now uniformly referred to as the S 76.
The S 76 A uses a four-bladed fully articulated main rotor head with single elastomeric bearings. Dual bifilar vibration absorbers, mounted above the rotor head are used to decrease vibration levels. The engines used on the S 76 A are the Rolls Royce 250-C30S. A four-bladed tail rotor provides directional control. Both the main rotor blades and the tail rotor blades have a titanium main spar with a Nomex honeycomb airfoil shape and fiberglass outer cover. The fuselage provides two compartments. The pilot compartment seats two and the passenger cabin seats up to 12. The fuselage contains extensive Kevlar and honeycomb components. The passenger cabin is available in three basic configurations. One is a 5-place corporate interior with 2 comfortable seats facing aft and a three- place bench facing forward. The second is a 12 seat utility configuration. This has three forward facing rows with 4 seats each. The third configuration is for EMS operators. This configuration puts two stretchers and four medical attendants in the cabin
First flight of the S 76 A prototype occurred in 1977 and certification to the standards of FAR 29 was obtained in late 1978. IFR and Category A certification were obtained shortly thereafter. First deliveries followed in 1979. A total of 284 S 76 A and S 76 A Mark II were delivered before production of this model ceased in 1989.
