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Laying the Groundwork

The CO2 standard for new aircraft provides a simple answer to a complex question

The successful resolution of discussions at the next ICAO Assembly will be vital to aviation’s environmental ambitions.

The debate on market-based measures will be complicated. But aviation has an excellent track record in collaborating to solve environmental questions. At the ICAO 37th Assembly in October 2010 the development of a new emissions standard was requested from the Committee on Aviation Environmental Protection (CAEP). The first step—a new metric that will measure CO2 emissions from aircraft and so underpin the new standard—was agreed by CAEP last year.

The industry has been pushing for a CO2 standard for some time as another tool for aviation to achieve its environmental goals. And having a new metric to measure CO2 emissions from aircraft is a significant achievement given the complexity and the many parameters involved. The metric will take a specific point in cruise, which relates to the maximum take-off weight (MTOW) of an aircraft and also its size.

Cruise control

While the final solution is elegant, it had to overcome considerable challenges. The devil was in the detail. A purely MTOW metric wasn’t appropriate as aircraft are used in different ways. Solving this issue required incorporating aircraft size and cruise fuel burn into the equation even if the calculations become difficult. In effect, the CO2 metric is common, irrespective of aircraft purpose or capability.

An even bigger challenge lies ahead, however. While airlines have a metric to measure their emissions there is no agreement on what is an acceptable limit on those emissions.
A number of elements affect the setting of an absolute CO2 limit including, technical feasibility, environmental benefit, cost efficiencies, and the impacts of interdependencies.

“A major area of debate is whether the standard should apply to existing aircraft types in production,” says Thomas Roetger, IATA’s Assistant Director, Environment Technology. “This would have significant implications for the industry. It could prevent the aircraft manufacturers from introducing fuel-efficient modifications within the production line, because these would require a costly certification.”

Clearly, this would be counterproductive in terms of emissions reduction. On the other hand, airlines are concerned that valuable assets would depreciate very quickly if their aircraft do not meet the new standard.

“This really revolves around the discussion on whether the new standard should be technology-forcing or technology-following,” explains Roetger.

Essentially, a technology-forcing standard could put the necessary technology in the hands of only one manufacturer for some time. This would distort competition and present airlines with a monopoly for some aircraft categories. It is widely accepted that it is best to take the best commonly available technology.

Collaboration can work

The aim is to agree on the CO2 limit by the CAEP Plenary session in 2016, which would allow for the limit to be passed at the 39th ICAO Assembly later that year. Once agreed at the ICAO Assembly the limit will become an ICAO certification standard and aircraft manufacturers will need to adhere to it.

While a lot of work lies ahead, Roetger says the CO2 metric is a clear label of industry intent to reduce carbon emissions. It ensures not only transparency in an increasingly sensitive area but also that manufacturers make the best effort to design aircraft as fuel-efficient as possible.

“That will enable airlines to keep emissions down as part of the industry objective to achieve carbon-neutral growth from 2020,” says Roetger. “And just as important is the fact that the industry has managed to get this done. It shows we can collaborate effectively and it is a promising sign for the environmental debates that will happen at the next ICAO Assembly.”

Making noise about getting quiet

The new noise standard is 7db lower than the previous standard. New widebody aircraft will
need to meet the new limit by 2017. Regional aircraft have until 2020. Known as Chapter 4, even though it is in fact the fifth standard to be agreed, the new limit has come round twice as fast as the previous upgrade in the standard and is twice as stringent, clearly demonstrating aviation’s commitment to reducing its noise impact.


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