Initially the S-92 was conceived as a large cabin Superhawk, with a gross weight of 22220 lbs. The gear boxes and dynamic components of the S-92 were conceptually designed to be utilized on future upgraded versions of the H-60. As such, the baseline designs began with current, at the time, H-60 components. At the time, Sikorsky already had operational data from more than 2,000,000 H-60 flight hours. As the S-92’s gross weight increased, changes were made to the system. Two of those changes were to increase rotor speed from 258 RPM to 271 RPM (>5%) and to increase in main rotor diameter (53.66 ft. to 56.3 ft.). These changes combined to provide some of the additional lift required for the higher gross weight. I have to believe that MGB vibratory signatures changed from those historically seen on the H-60.
Additionally, system changes were made to provide for better maintainability/supportability. The location of the oil filter assemblies were relocated to allow for servicing from the top rather than from inside the cabin.