Carbon-fiber reinforced plastics – also referred to as carbon fiber composites – are an indispensable part of aircraft manufacturing. Being particularly light and stable, they are ideally suited for the aviation industry. However, there is one unavoidable negative effect associated with their use in the production of aircraft components: the action of cutting the prepreg material, that is, carbon fiber web pre-impregnated with synthetic resin, produces large amounts of waste. Within the Pilatus Group alone, over six tons of this high-quality material have to be disposed of every year, unused.
Together with researchers at the Lucerne University of Applied Sciences and Arts and inspire AG, a strategic partner of the Swiss Federal Institute of Technology ETH Zurich, Pilatus is investigating whether this production waste can be directly recycled back into the aircraft construction process. The research project will last 32 months, during which time it will establish the scientific and practical basis for possible application in the future. The initiative for this study stems from the research community, but Pilatus, as an industrial partner, can provide the materials, the production environment and the expertise to test the idea in realistic conditions – thereby acting as a crucial bridge between the research laboratory and possible future application in aircraft production. “The project started as a result of intensive interdisciplinary discussions between all partners,” says Dr. Jan Kraner of the Lucerne University of Applied Sciences and Arts. “This joint process was key to moving from the idea to its implementation.”
Supported by Innosuisse
The project has received significant support from Innosuisse, the Swiss Innovation Agency. This body selects and promotes projects in which business organizations join forces with research partners to develop new processes or products – with a focus on direct benefits for industry. “The fact that Innosuisse chose to allocate a substantial financial contribution to the study piloted by the Lucerne University of Applied Sciences and Arts, inspire AG and Pilatus, is a reflection of its ecological, economic and technological relevance,” says Urs Thomann, Director Technologies, Processes, Sustainability at Pilatus. “At the same time, close cooperation with our research partners creates ideal conditions for exploiting the potential of high-value waste materials to even better effect, and for quickly putting new solutions into practice.”
From scrap to new component
The project focuses on a novel approach: firstly, the sticky prepreg scraps are heated in a controlled manner, causing them to lose their adhesive qualities, allowing further processing by machine. They are then cut into small pieces and transformed into new components using a special pressing process, before being hardened. This approach is new in aviation, as there is currently no established industrial method for directly transforming unused prepreg waste into new components.
This project is relevant to Pilatus for several reasons: “Firstly, recycling this material provides an opportunity to significantly reduce waste from our own production operations. Secondly, it may be possible to replace certain aluminum parts with carbon parts, generating savings of up to 36 tons of aluminum per year,” comments Urs Thomann. Using fewer materials not only means less environmental impact during production, but also potentially lighter aircraft – and every kilogram saved is beneficial in terms of reducing the carbon footprint.
At the same time, the project addresses a clear market trend: recent surveys indicate that reducing the ecological footprint is now an increasingly important consideration in aircraft purchasing decisions, and is likely to become a decisive criterion for a growing number of customers over the next five to ten years.
The collaboration with the Lucerne University of Applied Sciences and Arts and Innosuisse has already revealed the potential inherent in recycling high-value materials. For Pilatus, the project is a concrete step toward optimizing material use, reducing waste and actively shaping innovation. It is also a good example of the general need for “thinking outside the box” in that we need to see waste materials, which tend to have negative connotations, more in terms of valuable resources. This not only has a positive ecological impact, it also turns them into a profit-related economic factor. Together with our research partners, Pilatus is therefore helping to create an important stepping stone on the path to a true circular economy in aircraft production – and to more sustainable use of valuable resources. Over the next few years we will see whether the project delivers a solution and a successful outcome.
