Conceptual Design and Analysis of Hybrid Composite Power Gearing in a Fielded Drive System Configuration

Rotorcraft drive systems are continuously assessed for opportunities of improvement, with increased power at reduced weight as a primary motivation. A key area of interest is the use of composite materials in drive system configurations. Composites can be significantly lighter than metallic components currently in use. Rotorcraft transmissions can leverage weight reduction with hybrid composite gearing that incorporates metallic features (for high load elements such as the gear teeth), while using composites for lower stress features. While the weight benefits of hybrid composite gearing are significant, specific challenges require attention before the benefits can be realized in an advanced vertical lift drive system. This research effort, conducted under the Revolutionary Vertical Lift Technology (RVLT) project, identified an advanced drive system configuration, developed conceptual designs with hybrid composite power gearing, identified the technical challenges with hybrid composite power gearing, and provided recommendations for overcoming specific, technical challenges. The integration of composite materials in advanced drive systems proves to be a promising approach with improving performance.