Rolls-Royce is developing a composite fan system for deployment in future civil gas turbine engines. The primary aim of a composite fan system is to deliver a significant weight saving, which enables substantial improvements in specific fuel consumption (sfc), thereby contributing to reduced emissions and achievement of the ACARE targets. It is predicted that manufacturing major fan system components (blade and case) from composite material will save approximately 350 kg in weight per engine (based on Trent 1000 engine size), which equates to a saving of 150 tonnes of CO2 emissions per aircraft per year. There is far less material waste in the manufacture of a composite case, with >85% of the raw material in the final product, compared to about 15% for a metallic case. The method of manufacture of a composite case also consumes significantly less energy, primarily due to the lower processing temperatures. This was a collaboration between Rolls-Royce and GKN Aerospace. The project successfully demonstrated Composite Fan Case manufacturing capability on representative development equipment, and identified the additional work required to be able to demonstrate manufacturing capability on production equipment. Composite fan cases for the system level engine test programme were manufactured through this project. A reduction in the cost of the composite manufacturing method has been achieved through process optimisation and development of automated methods for the composite fan case. The project is an enabler for the next generation of aero gas turbines and offers enhanced product competitiveness through reduced engine weight, leading to reduced fuel burn and hence lower environmental emissions. The development of the method of manufacture has reduced the process cycle times, with opportunities for further reductions, driving a cost-effective solution. The knowledge gained in this project can be applied to many composite applications in the future.