Braiding/RTM Technology for Construction of V-22 Canopy Frame

The present V-22 canopy frame is made of titanium. Performance advantages of composites are clear but anticipated high manufacturing costs kept composites from being applied to V-22. The size and geometry of the frame is not amenable to traditional hand lay-up of preimpregnated materials. As an alternative, Foster-Miller proposes to braid dry preforms for resin transfer molding (RTM). Our Phase I investigation will concentrate upon establishing a practical, functional design. We will take a balanced approach that builds upon existing braiding technology. We will also investigate the suitability of intersecting and 3D preforms. The cross-sectional size of the canopy is ideal for braiding. The principal challenge facing braiding or any composites fabrication process is to efficiency transfer load at joints. Ideally, fibers should be continuous at intersections. We have produced a +/-45 degree (or other bias) - continuous fiber through the intersection structure. We believe this accomplishment is unique in the industry. As our baseline for the canopy frame we plan a double lap joint configuration. We will also develop two advanced options which will include through-joint fibers. One will be large preform sections that include at least one integral joint. The second will either be a one-piece construction or the lowest number of single preform segments possible. Foster-Miller has developed concepts for this proposal with input from a V-22 prime contractor Boeing Helicopeters. If a Phase I is awarded, Foster-Miller will pursue additional input from Boeing throughout Phase I.