Building a new airliner is one of the most technically challenging design projects on the planet. An aircraft requires a decade of development, with every last bolt and rivet undergoing careful scrutiny to ensure it meets the highest standards of quality and safety, as well as whole libraries of regulations to comply with. All this is undertaken against a backdrop of ruthless commercial competition and uncertain economic conditions, with a long list of customer demands that need to be met.

More than ever before, an airline needs a strong brand identity, from its advertising and graphics down to menus and uniforms. Up in the air, the language of interior design takes on a whole new dimension. Airbus knows that flexibility is a core requirement in a modern aircraft. When the A350XWB began development back in 2004, the principle design characteristics was that this was a wide-bodied jet, with space for nine generously-sized economy chairs in each row (each a class-leading 18in wide), together with more baggage storage and bigger windows.

The increase in scale has been offset by a huge investment in efficiency, spearheaded by the extensive use of carbon-fibre-reinforced polymers for wings and fuselage. The strength gains and weight savings translate to vital fuel efficiencies, critical in the margin-driven world of commercial aviation.

Space and light are also dominant themes in the interior, and at Airbus' own technical and design studios at its German headquarters in Hamburg, teams have toiled over mock-ups, setting out the ways to make the best in class cabin architecture work for the demands of the world's airlines.

Ingo Wuggetzer is in charge of cabin innovation at Airbus, exploring the ways in which customers - the airlines - can go about creating brand identity without compromise, while also retaining the legendary Airbus design language. 'We started with a concept pitch about the cabin vision,' he says, explaining how the initial designs were very consumer-driven for the outset. New technology helped every step of the way. 'The most important innovations are about spaciousness,' he continues. 'We used a lot of tools, elements and technology to make it work in terms of perception.' The most important new feature is the lighting. The A350XWB is a 100 per cent LED aircraft, with over 30,000 LEDs throughout the cabin.

Paul Edwards, Airbus' head of industrial design, points out that the system plays a key role in the cabin design. 'It offers the airlines the opportunity to differentiate,' he says. 'There's a choice of over 32 million different colours, and the system is also fully dynamic, which means the airlines can choose different scenarios that move from front to back, from side to side and even across the cabin diagonally. Not only that, the LEDs let the designers highlight certain areas. 'We can make the best opportunity of our signature details, such as the grip rails and the recessed lighting, which helps to promote the airline’s brand.'

In addition to the plethora of long-life, ultra-bright LEDs, each A350XWB has another core lighting element. 'The ‘dome’ lighting feature drew inspiration from the artist James Turrell,' says Wuggetzer. 'It's designed to wash the surface with lighting to create a really enhanced sense of space.' The dome is an almost architectural element, blurring the edges of the cabin and creating an expansive sense of space right through the aircraft.

'There are other new innovations in the A350 cabin,' Edwards continues. 'We have larger overhead bins, which allow our passengers to bring on more baggage than they have in the past, and we also worked a lot on window size.' Most importantly, all of these elements are presented in such a way that every carrier can make the most appropriate use of them. 'It's a platform approach with plug and play possibility to make it work for every individual airline,' Wuggetzer says. 'It’s a very efficient way of coming up with an individual product for our customers.'

The A350XWB's flexibility is achieved through the combination of space and a modular approach to the 'monuments' – the wardrobes, bathrooms, control centres and rest areas that have to be slotted in among the seating. 'You cannot separate innovation, design and comfort, and spaciousness influences your perception of comfort,' says Weggetzer. 'We try to make all the surfaces very clean and calm using new materials and new finishes - in the end it provides additional comfort for the passengers.'

Another key development is in-flight entertainment, an area where consumer technology has rapidly overtaken what was available in the air. 'Our research shows that it's all about connectivity,' says Edwards. 'It’s about being able to bring your own device because today’s consumer is always switched on and they want connectivity. The technology is getting smaller and it’s all about connectivity, about Wi-Fi and high definition screens.'

For Edwards, the A350XWB epitomises the Airbus approach to design. 'Our design language is based on our European history and heritage, and therefore in essence it’s very classical,' he says. 'It will stand the test of time and be more relevant for longer. We use themes such as making elements appear to float within the cabin, with parallel lines and continuous surfaces.'

To ensure these fine lines and elegant geometries can be easily translated into the myriad branding schemes worn by the world's carriers, Edwards and his team have developed a portfolio of seven key themes. 'The themes help us focus the airlines on the choice that’s exactly right for them and ensure that their brand is very clearly and directly communicated,' he says. 'And the range of materials will suit any airline’s business model, from a low-cost carrier all the way through to a luxurious legacy carrier, offering very rich colour schemes and textures and fabrics or even timbers with a variety of luxurious colours and grains.

'The design language offers differentiation, consistency and quality,' says Edwards, 'From an airline’s perspective, it offers a neutral canvas, a canvas on which they can apply their brand and really differentiate themselves from the competition.' The A350XWB cabin is a finely balanced piece of industrial design, made all the more remarkable by its place in the heart of a 21st century airliner.

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