An Overview of Advancements in Helicopter Transmission Design

: The fabricated stainless-steel housing provides a lightweight, high- temperature capability, improved life cycle cost, corrosion resistant approach to helicopter gearbox housing application. The thrust-carrying cylindrical roller bearing offers a viable solution for high-speed operation under load conditions that include both thrust and radial loads. The HCR buttress-tooth- form gearing demonstrated superior strength over the baseline standard spur tooth form regardless of material selection; also, CBS-600 is suitable gear material for high-temperature operation. This investigation presents the helicopter transmission designer with three advanced components to use as design options and an advanced hot-hardness gear material to use after its design allowables are established.