Efficient technologies for the fuselage structure - Airbus
How can your own products be optimised to increase the benefits for the customer? This is certainly a question that every company asks itself. In aviation, one answer is almost omnipresent: you have to reduce the weight of the components. And if this goes hand in hand with a more cost-effective manufacturing process, then you've won twice over. This is exactly what Airbus has set out to do.
"Years ago, we at Airbus had the vision of creating a new state of the art for fuselage components," says Anna Bauch, Head of R&T Development and Partnerships Germany at Airbus. "On the one hand, we researched new CFRP technologies and, on the other, introduced 3D-printed metal components into our aircraft." At first glance, CFRP, i.e. carbon fibre-reinforced plastics, and 3D printing of metals do not appear to have much in common. However, the engineer believes that both are predestined to be used in the search for new technologies for weight-optimised fuselage structures.
Less complex components save weight and costs.
In LuFo V-1, the aviation giant from Hamburg therefore launched IMPULS-Rasant. In the IMPULS joint project, the partners were looking for innovative, cost-saving solutions for CFRP fuselage structural components that could be implemented in the medium term. RASANT was part of this and stands for "Fuselage components based on new technologies". Airbus had set its sights on the frames. These form the basic structure of the aircraft. They provide stability and "carry the skin", which is attached to them via clips. The door frame ribs were of particular interest. This is because high loads occur in the area of the doors, which in turn is reflected in the manufacturing processes.
"Previously, the frames and clips were manufactured separately," says Anna Bauch. This means that many components had to be attached to the prefabricated frame. This production-heavy process resulted in a complex component. "At IMPULS-Rasant, the project team has now developed a CFRP integral frame," she continues. The clips are already on it. "We now have far fewer components, which not only reduces complexity, but also saves weight. Together, this in turn leads to a significant cost advantage."
Airbus S.A.S.
We have reproducibly proven that our process fulfils the high requirements of aviation.
Not carbon fibres, but metal structures were the focus of another LuFo project with which Airbus and Premium Aerotec wanted to optimise fuselage structure technologies - ALM2AIR. ALM stands for Additive Layer Manufacturing, also known colloquially as 3D printing. In the project, the teams had set their sights on the powder bed process. In this process, a high-energy jet travels over a bed of powdered metal. The metal melts at the points that will later become the wall. As soon as it solidifies, it forms a layer of the component. The bed is lowered slightly and the process starts again. The workpiece is now built up layer by layer. In this way, even the most complicated shapes are possible, which would be unthinkable using conventional production techniques such as milling.
3D printing using the powder bed process is nothing new in itself. But using it to generate components for a large civil aircraft is. "A major challenge was to investigate, define and constantly optimise the material and component characteristics in such a way that we meet the high requirements of aviation," says Anna Bauch. The teams therefore scrutinised everything from the powder grains to the surface properties of the final component. "The second challenge was to ensure that this could be reproduced," she continues. "Because we had to prove that it wasn't just a one-off effect, but that we could achieve the material and component characteristics again and again."
LuFo helps immensely to bring the right partners to the table for a project.
The effort and perseverance with which the teams went about their work has paid off. The CFRP integral bulkheads from IMPULS-Rasant now fly as standard in the A350. And ALM2AIR and subsequent LuFo projects resulted in the first components manufactured using the metallic powder process that Airbus incorporated into a civil aircraft. For example, the double-walled fuel line for the tanker kit in the A400M and the hydraulic distributor in the brake system of the A320 are now 3D-printed.
LuFo, says Anna Bauch, has contributed significantly to such successes. "I'm a child of LuFo," she says and laughs. "During my dissertation, I worked on a work package for a LuFo II project, which brought me to Airbus, where I immediately took over the technical management of another LuFo project." She has realised this time and time again: The funding programme makes it easy for the right partners to come together for projects such as IMPULS-Rasant or ALM2AIR. "And the financial support gives us the opportunity to concentrate on such topics in terms of personnel. This creates a time advantage that should not be underestimated."
Text: Kai Dürfeld
Projektträger Luftfahrtforschung
Contact:
Airbus
Dr. Anna Elisabeth Bauch
E-Mail: anna.bauch@airbus.com
www.airbus.com