Hybrid Composite Sandwich Structures for the Transportation SectorsFor transport applications, the benefits of composite materials in terms of lightweighting, life cycle costing and crashworthiness have been well demonstrated by high technology sectors such as aerospace, motorsport and defence. However, one of the barriers to the more widespread adoption of composites by the mainstream land transportation sectors (e.g. trains, trams, buses, trailers, etc.) has been the availability of robust, cost-effective design and processing technologies for the manufacture of large structures. Between January 2000 and September 2004, the HYCOPROD project worked to address this deficiency.Specifically, HYCOPROD focussed on the development of a number of enabling technologies for composite sandwich materials. These included:• The ongoing development of the “tied-core” sandwich concept, a lightweight structural material system that combines excellent static stiffness and strength performance with stable, large displacement, high energy (crashworthy) failure modes.• A tool to simplify the analysis of structures designed and manufactured from the tied-core sandwich concept (HYCOTOOL).• Manufacturing quality procedures for the robust production of composite vehicle structures, including new measurement methods relating to composite processing.• Non-destructive examination techniques for assessing the fitness for purpose of tied-core sandwich structures.In order to investigate and validate the application of the above enabling technologies, seven demonstrator vehicles and components were designed and manufactured within HYCOPROD. These included a rail vehicle cab and carriage end, a refrigerated semi-trailer, a bus door and bonnet, a tram bumper, and a horse box. Overall, these demonstrators validated the anticipated benefits of composites in terms of lightweighting, parts reduction and improved crashworthiness. Furthermore, a majority of the demonstrators were estimated to be cheaper, or no more expensive, than conventional metallic solutions.