Make or break?

By Guy Bird for Aircraft Interiors International, May 2009

Aircraft seat manufacturing needs a shake-up in ambition, technique and innovation according to experts both inside and outside of the industry. But where will the change come from and what form will it take?

“You can’t keep excusing the aviation industry regarding change on the basis that it’s tricky. It’s been like swimming in treacle in the last decade”. Not the words of an industry outsider, but those of Joe Ferry, head of design at Virgin Atlantic on the frustration he’s often experienced with the aircraft seat manufacturing industry during his career. Indeed back in the late 1990s he famously persuaded Virgin to set up the Reynard Aviation business specifically to prove the production feasibility and manufacture of his groundbreaking Virgin upper class flatbed seat after existing suppliers said the design couldn’t be built.

So where does Ferry feel the aircraft manufacturing inertia comes from? “I’m not going to defend them but I do understand. Essentially they’re cottage industries dealing in low-volume, highly bespoke products with incredibly stringent certification requirements – that puts the auto industry in the dark – and they work in a very restricted business environment with only a few aircraft suppliers. Given this, it’s hard to attract the best staff – they’d rather be in Formula 1.”

“I’m not going to defend them but I do understand. Essentially they’re cottage industries dealing in low-volume, bespoke products with incredibly stringent certification requirements and work in a very restricted business environment. Given this, it’s hard to attract staff. They’d rather be in Formula 1”

He’s not alone in his concerns. Howard Guy of independent design consultants Design Q – with its automotive background but now a large aerospace business too – sees a similar picture: “Things are basically still being done the way they’ve always been done. Vacuum forming is one manufacturing example. It has a 50% scrap rate, high labour rates and the finished product still looks awful.”

Guy says some aircraft seat legs are still CNC (Computer Numerical Controlled) 3D machine tooled out of a billet of metal, and if the seat crash-tests badly after being “thrown down a sled” they are modified and made again. Such processes seem old to him compared to other industries where simulation software programmes can help designers and engineers virtually evaluate and optimize the ability of any component before it becomes ‘real’, as he explains: “In the car business the process is different. Everything is tested electronically before you ever test the physical part.” There is a high initial cost to such intense early virtual feasibility which can require bigger volumes to make sense – Guy cites a notional example of £2m or so to tool up for a new pair of car tail lights – but reckons the pay-off that can result from this intensive early work is a final piece price of only £10 per light.

Such economies of scale don’t work in the same way for older aviation seat methods says Guy: “It could cost £500 to machine a seat leg but if you make more of them they don’t get much cheaper. 20 years ago the car industry was the same but now it is the norm to use electronic design processes.” Indeed, to demonstrate just what might be possible DesignQ recently showed its Cobra concept seat featuring an injection-moulded support beam, which would normally be machine tooled.

Mike Gilmore of ARRK, consultants to the likes of Bentley, Ford and Lear believes the lack of frequency in aircraft seat replacement cycles could also be a problem in terms of development as many have to survive 10-15 years’ punishing service while cars are generally facelifted every three years, so innovation can arrive quicker. “With automotive seating the optimization programme for the future facelift kicks in as soon as the current seat is signed off for production to see if parts can be merged, made lighter or reduced in number. This doesn’t happen in the aircraft industry,” says Gilmore. DesignQ’s Guy thinks this status quo stems from a lack of competition in the aircraft seat manufacturing industry with demand from airlines recently outstripping supply, citing examples of four-year waiting lists and 20,000-unit minimum orders stipulated by some seating suppliers.

Sitting in the cheap seats

The result of these old techniques and market situation has been until very recently, seats – especially in economy class – that don’t bear good comparison with those in many other types of transport. ARRK’s Gilmore cites the disparity between driving to the airport in a low-cost Ford Fiesta with its slick Motorola phone-inspired dashboard and well-bolted together soft-touch interior and then stepping into a low-cost short haul carrier’s economy seat: “The raw edges of the plastics, and the way the cushions lift off when you hold them – they wouldn’t be allowed in cars.”

“You can tell how good an automotive interior is when you get in a rental car with 20,000 miles on the clock. It will be knackered”

Defending aircraft seat manufacturers’ position Tom Plant, B/E Aerospace’s VP and general manager for seating products says the aero vs. auto comparison is not a fair one as aircraft seating has to do so much more than car seating. This includes passing incredibly stringent material flammability testing to greater cantilevered load bearing, not to mention a greater overall robustness in order to survive the wear and tear that hundreds of thousands of customers’ sitting, standing on and generally yanking about brings. As Plant comments, “you can tell how good an automotive interior is when you get in a rental car with 20,000 miles on the clock. It will be knackered.”

It’s true too that the end user of an aircraft economy seat does not have the same personal attachment to the product and experience that a private passenger car owner would have either. Private car owners tend to look after their seating better because they own the product and have to live with it every day – not just interact with it for holidays or occasional short trips. Nonetheless, some airlines – especially international long-haul carriers where the customer will be spending more time and money – see the benefit in higher quality economy seats. The Recaro-supplied CL3610 seat for Qantas’ Airbus features exposed carbon fibre seatback shells – an aesthetic USP for Qantas suggested by its creative director Marc Newson – to bring a high-end sports car atmosphere to aircraft. And it’s real carbon fibre too, not a fake look-alike film. The seat is also notable for its emphasis on lightweight materials.

Lightening the load

The current economic crisis and sky rocketing price of oil in 2008 – though stable again at present – has focused the minds of all transport industries on the need for better fuel efficiency to be more cost-effective. The aircraft seating industry has always had a greater emphasis on weight-reduction than the car industry as B/E’s Plant points out, “I can pick up a triple economy class seat and lift it comfortably above my head but a single car seat would be very different.” But further weight reductions in the interior of the aircraft are still possible through the use of lighter-weight materials and new production techniques. Plant says historically steel, aluminium and plastics have been used but sees previously too-expensive high-end grade aluminium going into B/E’s products. He also sees the potential for other lightweight materials like titanium to replace steel in structural areas and carbon fibre and various composites for secondary structures and various aesthetic components.

Phil Hall of Cologne-based Composite Designs is another consultant with an F1 motor racing background looking at the aviation industry with interest. Unsurprisingly given his company’s name, he’s a strong advocate of composites. He strongly believes in time they will replace conventional materials, saying: “It has to happen, as you can only go so far with aluminium, steel and plastics. They are never as cheap as aluminium but always lighter”. Hall is looking to launch a concept at the 2010 Hamburg show with composite as a primary structural part and is predicting a weight saving of 50% on that part alone.

Early adoption danger

Seat supplier Recaro has already commercialised a carbon fibre seat – the CL3610 – with the material used in the shells, seatback, backrest frame and unusually in a primary structural beam too. But it was not successful in this latter area as Hartmut Schürg, VP of Product Development, Recaro Aircraft Seating concedes: “We were able to certify it and sell it but it was too expensive to make. Great weight savings are possible with carbon fibre but it has limitations in 16g tests.” Schürg says part of the problem behind the increased seat cost were certification rule changes brought in half-way through the development process that meant they had to do much more expensive testing and inspections than would have been the case with more conventional materials. So much so, for the CL3620 ‘facelift’ of the CL3610 seat, Recaro reverted back to an aluminium beam to make significant cost savings but – by reducing the part count – still managed to make the seat 15% lighter. Despite the setback Schürg is positive structures will be made of carbon fibre in the future and is working with universities and other research and development bodies to help understand the material better. Composite Designs’ Hall acknowledges that composites can be tricky in certain situations – like under twisted loads – but says it is just a matter of designing a composite structure in a different way. “When designed poorly, composites can cause big headaches. But we have 15 years’ experience in designing F1 structures tested to 60g loads so the current 16g loads of current aircraft certification is no problem.”

“We want the aviation industry to be better, slicker and smarter and if we see obstacles to that happening we’ll challenge them”

Hall says his firm is expert in ‘finite element analysis’ of composites – in basic terms working out how the material will behave under certain loads and stresses – but concedes metals are much easier to test as they exhibit similar qualities in all directions, as he adds: “With composites you need to tailor the structure according to what it has to do, it could be 1mm thick in one area and 2mm in others. More fluidity and mouldability of shape is possible with carbon fibre too without the need of a sub-structure to support it. That’s another selling point.” Hall does concede composites and carbon fibre still command a premium over other materials, although he says carbon fibre producers have been upping their output due to higher demand from airlines for aesthetic parts – but says ultimately airlines need to work out whether using composites is more costly than paying for the fuel to fly around the extra weight of other materials.

B/E’s Tom Plant believes real innovation will only come when airframes and their interiors are no longer designed independently, as he puts it “a more holistic approach.” Recaro is also moving forward with an integrated product development team using its knowledge of both automotive and aviation seating for advances to both industries. As well as innovating in materials Hartmut Schürg says its process has also changed, having started to use serious virtual simulation for almost two years now, as well as clay modeling and CAD. Despite the concerns of DesignQ’s Howard Guy regarding the industry he says the criticisms only come from wanting an ultimately stronger industry: “We want the aviation industry to be better, slicker and smarter and if we see obstacles to that happening we’ll challenge them. Now companies with automotive backgrounds are itching to get into the aviation industry given how hard things are in the car business, so there will be an inevitable knowledge transfer.”

Virgin’s Joe Ferry believes whatever material or technique is favoured in the future the end customer needs to be kept in mind by all parties concerned a bit more – from seat supplier to airlines – as he concludes: “Our customers are driving Porsches and BMWs and have similar interior expectations when they get on to our planes. However, the answer is not to beat up the seat manufacturers but for airlines and manufacturers to collaborate and slowly move the suppliers out of their comfort zone. Take risks with new products but don’t push them so far that the system breaks. After all it’s in the airlines’ interests for seat manufacturers to achieve and succeed.”

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