Blue sky thinking

Atkins | 06 Jun 2008 | Comments

Our cities are growing and a rash of new major economic centres is set to emerge worldwide. How will new and existing airports cope with demand, while keeping environmental and social impacts to a minimum?

Early in 2008, the General Administration of Civil Aviation in China committed to building 100 new airports by 2020 to meet soaring demand from freight and passenger traffic. Beijing alone required a bigger hub to cope with the 2008 Olympic and Paralympic Games, and the sheer size of its new terminal building – bigger than all of London Heathrow’s combined – literally speaks volumes. The need for greater airport capacity is reaching critical mass. Atkins has already won five government sponsored design competitions for new airport terminals in China in recent years, with more to come in the near future.

According to Robert Aaronson, director general of Airports Council International (ACI), a not-for-profit group representing the views of the world’s airports, the issue of capacity is also hitting airports in Europe and North America.

“The only solutions are to build more airport capacity and use existing capacity more efficiently,” he says. In its latest forecasts of global traffic, the ACI has identified a capacity shortfall of a billion passengers by 2020.

Clearly, the aviation industry – on the ground and in the air – will have to engage in some radical thinking if passenger demand is to be met, especially if it is to allay mounting environmental and social concerns.

On the ground

Aaronson believes a number of innovations will start to raise airports’ sustainability credentials over the next few years. In particular, he sees a growing trend towards solar electricity generation. “The large roof spaces of terminal and other airport buildings are ideal surfaces for installing photovoltaic cells, for example,” explains Aaronson. “A significant number of airports are already using this technology, and I think it will become increasingly popular.”

Airport design is already stepping up to the challenge. At London Heathrow Terminal 5, for example, combined cooling, heat and power technology provides around 85 per cent of its energy needs. Melbourne Airport in Australia has coated its terminal roof with a special paint that has cut air-conditioning requirements by half. Hamburg Airport, meanwhile, has designed its new Terminal 1 with a “thermo-labyrinth”, which uses the temperature of the ground beneath to cool and heat the building.

The immediate local impact isn’t only on the environment. Worldwide, the collective voice of those living near airports is getting louder as traffic increases. Areas such as the south-east of England and the Bos-Wash corridor of the north-east US are nearing critical mass. Pressure groups argue that sleeplessness and stress caused by excessive noise can lead to an increase in blood pressure, and higher risk of heart attacks and strokes.

Faced with such pressure, the industry has responded, says Aaronson, pointing to a rise in the use of fixed electrical ground power at airports around the world as proof of its commitment.

“A parked aircraft can plug into the airport’s electricity grid and feed off terminal air-conditioning, rather than have the aircraft run a small generator to provide energy while it is at the stand,” says Aaronson. “Numerous airports have invested in these units, which reduce emissions and noise. I think their use will become standard at all airports in the next few years.”

The optimism is shared by the people behind the Silent Aircraft Initiative, a project funded by the Cambridge-MIT-Institute and with support from major partners in the airline industry. Those involved believe its goal – to develop an aircraft so quiet that it can barely be heard beyond the airport perimeter – could become reality before 2030.

Model airplanes

With air traffic predicted to rise by another billion passengers by 2020, the aircraft will also need to innovate to improve efficiency and minimise their impact, in the sky and on the ground.

Roger Gardner heads up Omega, an academic organisation dedicated to studying the environmental impacts of aviation from a technological, scientific and economic perspective, and to develop strategies to reduce the environmental impacts and business risk.

“We’re trying to fill knowledge gaps and stimulate new ways of thinking,” Gardner explains. “If the industry is pursuing anti-environmental practices through competitive convention, then we have to highlight the flaws in the business model and explore greener practices.” Omega is, for example, working with the industry to examine barriers to introducing new technologies, and looking at the environmental implications of different business models – everything from route management to the size of planes.

“Why would an airline offer to fly us from London to New York, via Paris?” asks Gardner. “It doesn’t make any sense other than that it costs less. And that’s flawed, because it is fuel inefficient.”

The aircraft manufacturers, naturally, have a huge role to play. As head of aerospace at Atkins, Neil Kirk has worked with client Rolls-Royce to develop engines for the new Airbus A380 super jumbo and supported design on the aircraft itself. The industry, says Kirk, is facing up to its responsibilities to local residents and to the environment. “The biggest issue is greenhouse emissions, which give the industry a very bad press,” he says. Aviation contributes 1.7 per cent of global CO2 emissions and has been in the firing line.

But, according to Kirk, environmental issues are now firmly at the top of the aviation industry’s agenda. “The A380, for example, is 17 per cent more fuel efficient than a comparable aircraft, and the next generation after that will be even more so,” he says.

Work that Atkins is currently engaged with includes developing stronger composites, essentially plastics, as part of the UK’s biggest composite development programme. “Using lighter composite materials to manufacture aircraft will make a huge difference to fuel efficiency and emissions,” explains Kirk. In fact, experts predict composites could deliver a 20 per cent better strength-to-weight ratio than metal.

The burning issue

It doesn’t stop there. Kirk believes that, alongside innovations in noise reduction and improvements in aircraft efficiency, the industry must confront another major challenge – dependence on oil.

“The problem is the fuel used in aircraft is extremely efficient,” says Kirk. It’s light and you can carry lots of it.” It’s an issue that is currently challenging the brightest minds in the industry, including those at Atkins. “There’s no viable alternative to airline fuel at the moment, so it remains a massive challenge for the industry over the next few decades,” says Kirk.

While the industry may not have arrived at a definitive answer, significant steps are being taken. Virgin Atlantic recently flew one of its 747s from London to Amsterdam with a 25 per cent biofuel mix of coconut and babassu oil in one of its four main fuel tanks, and Airbus exhibited its fuel cell demonstrator aircraft at this year’s Berlin Airshow. Trials like these serve to highlight the need to move from kerosene to cleaner (not to say cheaper) alternatives. One potential alternative is use of “second-generation” biofuels, which are made from plant waste or algae, and therefore carry far fewer food crop issues. Airbus recently launched research into second-generation biofuels and the first flight to trial a mix of algae fuel is due later this year by a New Zealand 747.

Biofuel by itself isn’t the answer. The implications of turning over land used for subsistence farming to grow energy crops are rife with difficulty. But raising the issue for debate demonstrates the willingness in the aviation industry to engage in finding solutions.

Taking flight

A note of caution, though. As Gardner says, the ever-present issue of safety can act as a drag on innovation as the industry weighs up the acceptability of new technologies.

“The industry is dependent on research and development and it has a horizon of a decade or so,” he says. “But the manufacturers are led by the airlines and the airlines led by the customers, so passengers and the local community can act as a hurdle to any unproven technology. The industry spends billions on developing new products, but passengers still need to feel safe and familiar. Omega is testing the environmental viability of some emerging technologies that could offer a cleaner future.”

But it’s not just the planes and where they land that must be looked at. One less remarked upon aspect of the debate is how air traffic control (ATC) is organised. Europe has 30 separate ATC organisations governing flights. The result? According to the International Air Transport Association, traffic delays in Europe amount to a quarter-million hours of extra flight per year. Richard Branson is one of many advocating that the system be abolished and a single entity established to oversee flights, thus simplifying Europe’s congested skies.

In parallel, research has led to new thinking on how planes fly, moving away from the conventional method of landing – which involves a series of inefficient “step downs” from cruising altitude. At some airports, including London’s Heathrow and Gatwick, aircraft now use the “continuous descent approach”, essentially gliding into land from cruising altitude. Since aircraft burn considerably more fuel at lower altitudes, allowing a constant gradient descent at a low power setting would save thousands of pounds of fuel per flight.

What all this shows is that there is an appetite among all involved in aviation to make it cleaner, more efficient and less damaging to local communities. Given that the aerospace industry currently spends 15 per cent of its total turnover on research and development, and that airport design is now one of the main crucibles of sustainable development, the signs are good that this is one industry committed to and capable of maintaining sustainable development.

Case in point: Islamic influence in China

The unprecedented growth in China’s airport development prompted Atkins to enter some 10 competitions for new airport terminals in recent years, winning half.

“Some of these airport projects are already under way,” says Atkins’ director of urban planning and design in China, KY Cheung. “One is being completed in Yinchuan, which is in the only autonomous Muslim province in China. With this in mind, care was needed not only in the function of our proposed designs, but also in considering the cultural concerns of the local people. We brought cultural symbolism into the design, including the onion domes and pointed arches familiar to mosques.

“In this case, we were not repeating the gateways and arches typical of Chinese architecture. We used new steel bending methods so that the long span steel structures used the same motif as one would see in any mosque around the world. We also included these pointed arches as part of the original 3D concept for the structure. The result has a unique Muslim flavour, as well as a very modern structural concept.”

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