Traffic control could help cut emission from planes
The quickest way to cut emissions from aircraft could be better flight management rather than new technology, an Oxford University study has found.
Better air traffic control determining how, when and where planes fly could help quickly achieve significant emission cuts.
These include more direct flight paths to airports and less waiting to land.
These are the "low-hanging fruit" compared to technology improvements and existing biofuels, said Dr Chris Carey.
"And they are measures that governments could make a condition of using their airspace," said Dr Carey, aviation expert at Oxford's Smith School of Enterprise and the Environment.
Chris Goater of the Civil Air Navigation Services Organisation (Canso) agrees.
"Air Traffic Management plays an important role in reducing emissions," he says, pointing out that emissions could be cut by between 5% and 8% as a result of improved logistics.
Other initiatives should help the aviation industry ensure "emissions are reduced to 50% of 2005 levels by 2050", he said.
Cheap and easy
Better traffic control systems should also help aircraft reduce the time spent with their engines running while still on the tarmac, Dr Carey said.
At the same time, better flight control systems should help them spend less time flying.
"The inaccuracy of current control systems means planes must be given a wide berth to avoid collisions," he said.
"If that was improved, landing and take-offs could be quicker, stacking would be reduced and planes could fly closer together by taking advantage of prevailing winds, just as Concorde did."
Such improvements would be cheap to introduce quickly, Dr Carey insisted.
"They should be implemented as soon as possible if we are serious about cutting aviation emissions," he said.
Slow and risky
In contrast, technological advances, such as better engines or reduced weight, tend to take a long time before they have an impact, because aircraft have lifetimes of 30 years or more.
In the long run, innovations that help reduce drag will help reduce emissions, as might a shift away from fossil fuels towards biofuels made from algae.
"But none of those measures can be introduced quickly and most new technology is not retrofitable," said Dr Carey.
"These are all long-term innovations that we won't see for at least 30 years."
Moreover, investing in new technology is both expensive and risky, Dr Carey said.
"But major technological innovations are a massive financial risk because you could be making a plane that no-one's going to buy," he said.