Grant: Collaborative Research and Development Grants

This project aims at the development of tapered thermoplatic composite tail booms for helicopters which has the configuration of a tapered cylinder. It connects the cabin of the helicopter to the tail rotor, whose function is to control the direction and stability of the aircraft. The tail boom is subjected to a large amount of bending moments and stresses. For weight saving purposes, the tail boom is usually a thin walled tube. It is located in the wake of the exhaust gas coming from the engine. As such, it needs to be made of a material with sufficient high temperature performance. The tail boom has been made using aluninum which possesses the characteristics of light weight, sufficiently good strength, stiffness and temperature performance. The increased usage of composites in aircrafts by major aircraft manufacturers such as Boeing and Airbus has opened the way for more innovative usage of composites in airframe structures. The use of composites to make helicopter tail booms can translate into significant savings in terms of manufacturing time, and excellent fatigue performance. Thermoplastic composites such as carbon/PEEK offer very attractive characteristics such as excellent strength and stiffness, good temperature performance and reasonably large amount of data base. However technology for making composite cylinders using automated fiber placement process only came out a few years ago. The fabrication of tapered cylinders poses many challenges including the requirement to address the laps and gaps between layers, or curved fiber paths. This also gives rise to manufacturing, analysis and design issues. This project will address the stress analysis for design of the tail boom using thermoplastic composites, and issues related to the manufacturing of the tail boom using fiber placement technique. Properties of laminates containing laps and gaps (or curved fiber paths) will be studied and used for the development of the composite tail boom. Manufacturing, analysis and design techniques will be developed.