Introduction 9 (c) Figure 1.5 (continued)Examples of 3D woven preforms.(a)Cylinder and flange,(b) egg crate structures and (c)turbine rotors woven by the Techniweave Inc.(Photographs courtesy of the Techniweave Inc.). While a variety of components have been made to demonstrate the versatility and capabilities of 3D weaving,the reported applications for the material are few.One application is the use of 3D woven composite in H-shaped connectors on the Beech starship (Wong,1992).The woven connectors are used for joining honeycomb wing panels together.3D composite is used to reduce the cost of manufacturing the wing as well as to improve stress transfer and reduce peeling stresses at the joint. 3D woven composite is being used in the construction of stiffeners for the air inlet duct panels to the Joint Strike Fighter(JSF)being produced by Lockheed Martin.The use of 3D woven stiffeners eliminates 95%of the fasteners through the duct,thereby improving aerodynamic and signature performance,eliminating fuel leak paths,and simplifying manufacturing assembly compared with conventional 2D laminate or aluminium alloy.It is estimated the ducts can be produced in half the time and at two- thirds the cost of current inlet ducts,and save 36 kg in weight and at least USS200,000 for each duct. 3D woven composite is also being used in rocket nose cones to provide high temperature properties,delamination and erosion resistance compared with traditional 2D laminates.It is estimated that the 3D woven nose cones are produced at about 15% of the cost of conventional cones,resulting in significant cost saving.3D woven sandwich composites are being used in prototype Scramjet engines capable of speeds upIntroduction 9 Figure 1.5 (continued) Examples of 3D woven preforms. (a) Cylinder and flange, (b) egg crate structures and (c) turbine rotors woven by the Techniweave Inc. (Photographs courtesy of the Techniweave Inc.). While a variety of components have been made to demonstrate the versatility and capabilities of 3D weaving, the reported applications for the material are few. One application is the use of 3D woven composite in H-shaped connectors on the Beech starship (Wong, 1992). The woven connectors are used for joining honeycomb wing panels together. 3D composite is used to reduce the cost of manufacturing the wing as well as to improve stress transfer and reduce peeling stresses at the joint. 3D woven composite is being used in the construction of stiffeners for the air inlet duct panels to the Joint Strike Fighter (JSF) being produced by Lockheed Martin. The use of 3D woven stiffeners eliminates 95% of the fasteners through the duct, thereby improving aerodynamic and signature performance, eliminating fuel leak paths, and simplifying manufacturing assembly compared with conventional 2D laminate or aluminium alloy. It is estimated the ducts can be produced in half the time and at two￾thirds the cost of current inlet ducts, and save 36 kg in weight and at least US$200,000 for each duct. 3D woven composite is also being used in rocket nose cones to provide high temperature properties, delamination and erosion resistance compared with traditional 2D laminates. It is estimated that the 3D woven nose cones are produced at about 15% of the cost of conventional cones, resulting in significant cost saving. 3D woven sandwich composites are being used in prototype Scramjet engines capable of speeds up