On a higher plane

Boeing says that, far from being risky, its substantial use of composites in its 7E7 will make the aircraft more durable, reliable and efficient than using more conventional materials. Christopher Sell reports.

Is Boeing building up to something big for Farnborough? After a public bout of the jitters in the past few years the company seemed in confident and relaxed mood last week.

The progress made by Airbus on the A380, rival to Boeing’s fledgling 7E7, or Dreamliner project, will always be cause for concern (for Boeing or its investors), but that was not apparent in London last Wednesday when it announced the latest supply contract for the new aircraft.

There were bullish predictions of 500 firm orders for the 7E7 by the time flight tests begin in 2007, and a total of 1,500 sales in the next 20 years. Claims made by Airbus that Boeing has ‘rushed’ the development of the Dreamliner were also confidently brushed aside.

And in an interesting twist to the war of words on the future of air travel, Boeing for the first time took a less aggressive stance. Executives played down the competition with the A380, suggesting that the planes were not a threat to each other as they are suited to separate markets.

Michael Bair, senior vice-president of the Boeing 7E7 programme, believes the size of the A380 will only find a place in the top bracket, while the Dreamliner will be secure in the middle market – one that Boeing believes is worth $400bn (£219bn).

‘I think there is probably room for both,’ Bair said. ‘Clearly there is a requirement for big aircraft, but our studies have shown that it is not worth investing in a big aircraft.’

He added: ‘You should be careful when matching them up. A carrier looking for a big aeroplane won’t be looking at the 7E7 as an alternative. They are fundamentally different market places.’

So with Farnborough closing in on the radar, we might be forgiven for wondering what exactly Boeing is saving for its show-stopper. One executive said last week that he was ‘convinced’ that the Dreamliner will be flying the colours of a UK airline. Was he indicating that this would be sooner rather than later? Those orders will have to start coming in smartly if Boeing is to meet the 500 target by 2007. But are the airlines convinced by the Dreamliner? And what about those accusations that it will be too heavy and not as efficient as Boeing claims?

Boeing and Airbus stepped up their negative campaigning after Boeing criticised weight increases in the A380. Earlier this month in Toulouse, Airbus executives said that Boeing was relying too heavily on composite materials in the wings and body of the aircraft to reduce weight. They claimed that the design had been rushed through before the technology had sufficiently matured.

Colin Stuart, Airbus vice-president of marketing, said composites should be introduced with caution in aircraft design. ‘If you start to look at the various loads on composites [in an all-composite fuselage], it is absolutely the wrong thing to do.’

Current composite material is unsuitable for many areas of the fuselage, claimed Alain Garcia, executive vice-president of engineering at Airbus. ‘It’s perfect for tension and fatigue, but poor for compression.’

Boeing’s response was that composites, which account for 50 per cent of the weight of the 7E7, provide greater durability, reliability and lower maintenance, together with greater efficiency and less waste. Bair said the company was merely expanding the use of composites already exploited in the 777.

‘From the technical side we see very little risk. We have a long track record with this material. The risk we see is from the manufacturing side and how fast we can lay this material down to build the 7E7,’ said Bair.

Using the material enables the firm to build the fuselage in a single piece. This means final assembly of a Dreamliner will be just three days, as opposed to the 15 days it takes to complete a 777. ‘We are changing the design to optimise properties of composite materials,’ said Bair.

Boeing claims the reduced weight leads to a 20 per cent improved fuel efficiency and less impact environmentally.

‘The whole point of the 7E7 using composites is to reduce weight. You have immense strength anyway, and the kind of benefits you get are fuel efficiency, structural monitoring-type benefits and reduced cabin altitude [from about 8,000ft to 6,000ft],’ a spokesman said.

The company believes the Dreamliner represents the future of air travel based on point-to-point services to a wide range of destinations. The A380, however, is based on a hub-to-hub plan, believing that customers are primarily concerned with cost.

The Dreamliner’s reliance on composite materials, especially in the fuselage and wings, has opened up new design possibilities. Larger seats and windows, lower cabin altitude and higher humidity are some of the benefits singled out by Boeing. In fact 7E7 claims to have ‘the best fuel efficiency of any wide-body aircraft, which translates to fewer emissions’. Boeing further claims that advanced flight controls, breakthrough structures and aerodynamics will make the flight more enjoyable and comfortable for passengers.

For the 7E7 to produce 20 per cent greater fuel efficiency Boeing has incorporated a number of new technologies, including the common core system (CCS). Developed by Smiths Aerospace of the UK engineering firm Smiths Group, CCS is described as the plane’s ‘central nervous system’. It will consolidate into two cabinets the dozens of standalone computers usually found throughout an aircraft. These computers host the software that controls most of the aircraft’s avionics and other utilities.

Mike Grady, vice-president of civil and military transport, said the dramatic reduction in hardware would bring savings in money, weight and maintenance. ‘When you buy 20 computers you also need 20 power supplies,’ said Grady.

‘Then you need a lot of wiring, which is expensive and creates reliability issues.’ Instead of conventional signal wiring the 7E7’s CCS will use an advanced communications system called a ‘deterministic ethernet’ to link the various on-board systems.

The system will require minimum maintenance, and only a simple software upgrade would be required when new functions are introduced to the aircraft. The two cabinets offer ‘dual redundancy’. This means that one can support the other in the event of problems, Grady added.

At the Boeing conference last week, it was announced that Smiths had been selected by Boeing to supply the landing Gear and high lift actuation systems for the 7E7 in contracts totalling more than $1.6bn (£0.87bn). Smith’s landing gear work complements the landing gear structure work that will be done by Messier Dowty.

Smiths will provide the nose gear steering system, the brake control and indication system, and the main and nose landing gear/gear door actuation system.

Sir Michael Jenkins, president of Boeing UK, commented: ‘The UK contribution to the 7E7 continues to grow, underlining the importance of the British aerospace sector to Boeing and the value of Boeing to the British economy. This work, combined with that of Rolls-Royce, Messier Dowty and Cobham, indicates that the 7E7 is set to have a strong benefit to the British economy.’

At the conference John Ferrie, group managing director of Smiths Aerospace, said this would secure 100-plus jobs at a number of Smiths plants, including Cheltenham and Wolverhampton. Boeing has received an order from All-Nippon Air for 50 aircraft. This is Boeing’s biggest single order ever, according to Marlin Dailey, vice-president of sales Europe. He added that Boeing is in discussion with 30 airlines and Bair is ‘optimistic’ that the company could sell 500 7E7s.

Boeing has put this ‘phenomenal’ interest down to the price tag of $120m (£66m), the same as the 767. However, the 7E7 is capable of travelling 2,500 nautical miles further. It can also carry 16 per cent more cargo and cruises at Mach 0.85 rather than 0.80. In addition, the engine for the 7E7 will be one cycle ahead of the A380, its structural composites will be 20-30 per cent more efficient than aluminium, while advanced computation dynamic software will lead to a five to six per cent improvement in aerodynamic efficiency.

Such apparent technological advances led Bair to claim that ‘at any distance all three models of the 7E7 will be more efficient than the A380’.

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