Although lighter and more durable than conventional materials, the use of composites in the production of aircraft structures has been limited due to high costs. Now, a clever European SME has developed a new method for building a composite aircraft tail cone that will help get more efficient air transport off the ground.
Created by three ambitious student engineers and initially incubated through academic research grants, France's Coriolis Composites S.A.S is an innovative SME specialising in the development, marketing and distribution of fibre-placement technologies.
Coriolis' Chief Technical Officer Alexandre Hamlyn says the company started out as three young engineers who wanted to build better yacht hulls automatically. "We loved sailing," he says. "It's as simple as that." But within a few years, their involvement in the wider world of composites had grown by leaps and bounds, crossing sector boundaries and bringing Hamlyn and his partners to the forefront of a worldwide manufacturing field.
The use of composite materials in the aeronautics industry got a real lift in the early 2000s with the launch of the first 'all carbon' Boeing aircraft, the 787 Dreamliner. Then everything changed for Hamlyn and his team when they were approached by aerospace giant Airbus, which wanted to use Coriolis technologies to make their own composite-based aircraft components.
Mr Hamlyn says his company has never looked back. Now numbering over 40 highly skilled and enthusiastic staff members, his group works on a daily basis with major industrial and research players, including Daher Aerospace, the Netherlands' National Aerospace Laboratory (NLR) and Honeywell, and it is a key participant in the EU-funded Advitac project ('Advanced integrated composite tail cone').
Composites take off
For the aeronautics industry, production costs have always been the limiting factor in the use of composites. The conventional manufacturing method, which involves the manual stacking of pre-impregnated sheets of material followed by curing in an autoclave, is complex and labour intense, precluding a high level of parts integration and increasing costs. Assembly alone – for example, positioning, drilling and riveting – represents between 20 and 30 % of the total cost of this kind of manufacturing.
For the Advitac project, Mr Hamlyn says Coriolis is applying a more advanced method, developed by another EU-funded project called 'AUTOW'. Under this new method, a dry fabric is preformed into the component shape, placed in a mould, and then injected with resin and cured.
"Until now, this kind of more advanced fibre-placement technique has been limited by the trajectories that can be followed by robotic machines," he explains. "This is not the case with our method, which allows us to produce highly complicated and integrated parts."
Coriolis' state-of-the-art system for fibre-placement features poly-articulated robots and sophisticated software. Based on machines originally used in the automotive industry, the Coriolis robot will cost €1 to 3 million, while equivalent US-produced robots now cost at least €4 million.
All the pieces in place
"Our composite aircraft tail cone will be 10 % lighter and will not need fasteners," explains Mr Hamlyn, "meaning less-expensive materials are needed as well as simpler tooling processes, and allowing for increased operational efficiency, reduced noise, fuel consumption and nitrogen oxide emission."
Advitac represents a remarkable approach to advanced industrial research in the aeronautics sector, allowing small companies like Coriolis to play big roles, with more freedom to define their own work programmes and working closer to the exploitation end of the development and manufacturing chain.
Mr Hamlyn likes the approach, believing his company has gained valuable experience working with industry heavyweights, allowing it to anticipate end-user requirements, especially regarding material and process specifications.
"Advitac involves all the partners needed to find new solutions for the entire process chain," he says, "from design to production, including end-users, thus maximising the potential for results and, ultimately, success in the market place."