Design for Manufacturing – One-Piece, Fibre-Placed Composite Helicopter Tailboom

Abstract

Recurring cost has become a critical driver in the design of helicopter airframes, and although composite materials have become widely used in aircraft structures, the hand lay-up manufacturing process in many cases prevents these applications from being cost-effective. Automated manufacturing technologies promise not only reduced production costs but also higher quality, repeatable parts. The introduction of existing automated manufacturing techniques and technologies from industries such as the automotive sector into aerospace can be challenging due to the unique product characteristics as well as the stringent certification and quality control requirements of the industry. The aerospace industry is a low-volume, high value production environment where "hand-made" products are produced by highly experienced and qualified trades-people. Both metallic and composite components are subjected to precise manufacturing control and documentation requirements. The introduction of automated manufacturing technologies must be done in such a way as to respect these often demanding constraints. The introduction of automation to industrialized processes impacts not only the way parts are produced, but also the way they are designed. Successful composite design and manufacturing automation in the aerospace industry requires the engineering designer and analyst to become increasingly involved in the manufacturing of the product, as machine limitations and producibility become increasingly important drivers for design. This paper presents an overview of a development project intended to evaluate the effectiveness and benefits of the automated fibre placement technology through the design, prototype build and testing of a composite tailboom. The discussion centres on the "design for manufacturing" concept and provides a perspective on the project objectives, material and process selection and trade-offs, geometric and structural considerations, and component assembly and fastening.