Master process sheets for fabrication of CFC centre Fuselage parts for TEJAS (Light Combat Aircraft) - part-5

Advanced Composites Division has developed innovative techniques to manufacture stiffened bulk heads and sandwich panels. Special tools are established for stiffener layup that avoid the complex machining operation. The stiffeners are co-cured and co-bonded with the basic skin to gain the advantage of composite. The long experience in composite tooling enable ACD to use the sub tools in three pieces between two stiffeners that maintains straightness of the stiffener minimizing the thinning of stiffener web. As bulk head panels have so many cutouts and kinks and also the surface is non developable, the wastage of prepreg material is minimised by using the tape of different width. This innovative method of layup not only saves the material but also reduces the layup time and provides a wrinkle free surfaces. The caul plates needed for sandwich panels are obtained by derivative tooling concept. This method enhances the contact between the component and caul plate avoiding any resin rich or resin starved region. In addition a cushioning effect between the rigid tool and the component is given by a unique technology adopted by ACD. This has well explained in the process. This report describes the step-by-step procedure to realise the airworthy.~ composite component. The process and the toolings have been fined tuned keeping tb view of series production of LCA