Air traffic controllers plan route to fuel-saving flights
New technology and smoother routes help U.K. air traffic services save airlines 1 million tons of CO2 a year — and now they're aiming higher. Read More

This article first appeared at Business Green.
Aviation emissions are a problem. Currently, they equate to about 2 percent of total global greenhouse gas emissions, but they are expected to make up a much larger share in the coming years as global trade increases and other sectors start to decarbonize. EU aviation emissions, which represent a third of total global emissions from aviation, have doubled since 1990 and are predicted to triple by 2050 if unchecked.
The 2.2 million flights passing through U.K. airspace each year are responsible for putting around 23 million tons of CO2 in the atmosphere each year — roughly equivalent to the annual emissions of six coal power plants.
Reducing U.K. aviation emissions is win-win for the environment and the airlines — if less fuel is burnt, carriers are lowering their costs and pumping fewer emissions into the atmosphere. But how to address the problem? International talks at the U.N. have yielded only a set of voluntary pledges, and while the industry is investing in alternative greener fuels and more efficient aircraft, research by Boeing last year predicted the number of aircraft in service will double between 2011 and 2031, most likely pushing up emissions regardless of any fuel efficiency improvements.
One organization attempting to stall this growth of aviation industry emissions is NATS, the air traffic services company that controls U.K. airspace. Since 2008, NATS has been working toward smoother, more direct routes that use less fuel, and is saving around a million tons of aviation-related CO2 each year.
The improvements equate to $174 million in fuel savings for airlines and an average 4.3 percent cut in CO2 emissions per flight against a 2006 baseline, beating NATS’ target for a 4 percent improvement by the end of 2014. This is good news for Ian Jopson, head of environment and community affairs at NATS, as it means the company has secured a bonus payment from the airlines. NATS is the only air traffic services provider in the world to be financially incentivized to improve environmental performance and could have faced a penalty of $7.27 million if it failed to hit the 4 percent goal.
Now, Jopson is tasked with helping NATS hit a 10 percent reduction by 2020 with the stakes raised even higher. “We could potentially win or lose 1 percent of our turnover,” he admitted, rather more cheerfully than you might expect. “[But] it’s good news for me, because when you have bonus and penalties on delivery of a plan, then it gets on to the managing director and chief executive’s scorecards pretty quickly, which raises the profile through the organization.”
In the past six years, NATS has brought in over 300 airspace and procedural changes to improve flight profiles and to reduce fuel burn, ranging from removing barriers to flights in certain sectors of airspace, which enables more direct routes, to encouraging pilots towards more efficient flying, such as gliding descents into landing. Negotiating with the military to use its previously restricted airspace at certain times has saved 30,000 tons of CO2.

NATS next goal is to hit a 10 percent reduction in CO2 emissions per flight by 2020.
Technology also has played a role — a new software tool called GAATS+ was brought in last month to help controllers give more efficient profiles across the North Atlantic, saving a further 110,000 tons. The technology even takes account of aircraft losing mass as they burn fuel, which enables them to climb to higher altitudes that are closer to the optimal track and can take advantage of high winds.
Collaboration with counterparts in other jurisdictions also has helped bring down burn rates. The winningly named X-Man project — more prosaically, the Cross Border Arrival Management Initiative — involves asking other air traffic organizations to slow aircraft down so they spend more time cruising, which is far more efficient than circling holding patterns over airports. Just slowing down aircraft has taken more than a minute off holding time for every aircraft that holds around Heathrow.
Working out the savings takes a hefty dose of computing power. “Every aircraft that goes through our airspace has an environmental efficiency score — to compute those scores we have to analyze over a billion radar points,” Jopson said. “No one else does it to that level of granularity.”
But while NATS undoubtedly has achieved excellent results, the next push to deliver 10 percent savings is likely to get the circuits firing even more furiously.
Jopson is overseeing a $909 million “root and branch” redesign of the airspace in southeast England and above Manchester that he said will improve safety, capacity and environmental performance, through “enabling continuous climbs, more point to point routes, [and] strategically de-conflicting flows of traffic through that airspace.”
The skies above London and the southeast are some of the busiest in the world and Jopson is certain the London Airspace Management Programme is “probably the biggest airspace change we’ll ever undertake.” New, highly accurate satellite-navigation technology will enable aircraft to get closer to each other and closer to their more optimal profile without compromising safety.
Controllers also will be given better information to help plan more efficient routes. Currently, NATS can give controllers data about their environmental performance when they end their shift, but Jopson would like to get to a situation “where that information is on their control screen so they can make decisions on the best data about how environmentally effective their route selections are.”
However, a 10 percent saving remains a testing target. Jopson freely admitted when it was set he did not know if it would be achievable and that reaching it will require him and his team to come up with more ideas.
“Our projections show that even if we deliver all of those things, there will still be a gap to the 10 percent target for 2020,” Jopson said. “We’re thinking hard about where the extra 1 or 2 percent is going to come from.”
Teams of controllers and pilots are convened regularly to discuss how to tackle remaining inefficiencies, while Jopson also holds out hope further savings could come from working closer with other national operators.
It promises to be a considerable challenge — but you would hope if anyone can land something this big, it would be air traffic controllers.
