Research & development CFRP Developing a carbon fibre hybrid fuselage for multifunctional purposes - Developing a carbon fibre hybrid fuselage for multifunctional purposes ..................... p56 - Assessing the damage evolution of composites containing embedded fibre optics .................. p60 The Boeing 787 Dreamliner is an innovative aircraft that consists of more than 50% carbon fibre reinforced plastics (CFRP) due to these materials' low weight and exceptional strength. Using COMSOL modelling tools, engineers at Boeing research found that a metal foil inserted in a CFRP laminate can provide lightning protection for the aircraft structure. The purpose of this article is to explain how this laminate can be improved to create multifunctional materials that can protect the fuselage from lightning strikes while providing vibration damping and sound absorption effects. By Dr Yosif Golfman, R&D Engineer, Neo-Advent Technologies LLC C arbon fibre cannot mitigate the potentially damaging electromagnetic effects of a lightning strike. To solve this problem, an electrically-conductive expanded metal foil (EMF) can be added to the composite structural lay-up to rapidly dissipate current and heat in order to ensure the lightning protection of CFRP materials in the aircraft [1]. Carbon fibre coated with elastomers can reduce the vibration and acoustic effects. Japan researchers found that when covering CFRPs with elastomers, the Fig. 2: Sample for damping and acoustic protection damping loss factor changes from 0.01 to 0.100, thus improving vibration damping properties [2]. A thermoforming technology was developed for multifunctional layers. Spray technology can be more effective for shipboard and aircraft applications. A concept combining a tough sprayed epoxy bottom layer and a sound absorbing sprayed polyester top layer looks like a good alternative to open-cell polyimide foam insulation panels developed for the NASA [3]. Two traditional insulation materials - an EAR 3/8" material and Pyrotech 3/8" SP150 tiles - are presented in works [4] and [5]. Material requirements Fig.1: The Boeing 787 Dreamliner 56 jec composites magazine / No97 May - June 2015 Figure 1 represents the Boeing 787 Dreamliner, which includes 50% of plasticsbased parts. Noise Control Engineering LLC developed special requirements for multifunctional spray materials:http://www.jeccomposites.com/events/jec-forums-boston-2015