ATM projects seek greener future

Air traffic management initiatives around the world have environmental principles at their core, as Emma Kelly reports

1st Jun 2010


AIRE, ASPIRE and MINT are not just catchy acronyms but collaborative air traffic management (ATM) initiatives, all designed to deliver a greener future.

ATM improvements represent the greatest near-term opportunity to significantly reduce aircraft fuel consumption and emissions through improved efficiencies. According to the International Air Transport Association (IATA), for example, cutting flight times by just one minute per flight on a global basis would save 4.8 tons of carbon dioxide emissions every year.

The two biggest ATM modernisation programmes under way with environmental considerations at their core are Europe’s Single European Sky ATM Research (SESAR) and the United States’ Next Generation Air Transportation System (NextGen). Both are aiming to deliver ATM systems that will be able to cope with future traffic growth, while increasing operational efficiency and cutting fuel burn and emissions.

The environment is a priority for SESAR, Alain Siebert, chief of economics and the environment at the SESAR Joint Undertaking (SJU) said at the ICAO Colloquium on Aviation and Climate Change in May. The SJU is the management body comprising a public-private partnership established by the European Union to develop and implement SESAR.

The programme is intended to allowed EU skies to handle three times more traffic than they do now, improve safety tenfold, reduce carbon dioxide (CO2) emissions per flight by 10 percent and halve ATM unit costs, he said.

Wheels in motion

SESAR is one of the most ambitious and innovative research and development projects ever launched by the EU. According to the SJU some 1,400 engineers are now working on the programme and the modernisation of European ATM. By March, 75 percent of the almost 300 projects making up SESAR were under way.

SJU executive director Patrick Ky told delegates at the ATC Global show in Amsterdam in March that 77 airline experts have reviewed 120 projects assessing whether SESAR technologies and procedures are in line with their needs and expectations, while five associations representing pilots, air traffic controllers, handling staff and air traffic safety officials are providing operational technical knowledge and expertise.

The work programme this year is focused on information management – the development of information models and software allowing flight data exchange between the aircraft information management systems and airports; route assignment and guidance; and advanced surface movement guidance and control systems. All SESAR improvements are being demonstrated in the operational environment.

The US Federal Aviation Administration (FAA) NextGen project is similarly aimed at providing new capabilities to make air transportation safer and more reliable, improve the capacity of the National Airspace System and reduce aviation’s impact on the environment, Maria DiPasquantonio of the FAA’s air traffic international office told the recent ICAO meeting.

NextGen includes automatic dependent surveillance-broadcast (ADS-B) which is set to be implemented nationwide from 2013, performance-based navigation, System Wide Information Management (SWIM), data communications and NextGen Network Enable Weather (NNEW).

“NextGen’s vision is to provide environmental protection that allows sustained aviation growth,” says DiPasquantonio. This will be achieved through quieter, cleaner and more fuel-efficient flights; the use of alternative fuels, new equipment and operational procedures designed to lessen the impact on the climate; and more precise flight paths to lessen the impact of noise.

At the 2007 Paris Air Show, Europe and the US came together launching the Atlantic Interoperability Initiative to Reduce Emissions (AIRE) which was aimed at reducing carbon dioxide emissions on transatlantic services through the use of optimised ATM measures and procedures. It was based on the straightforward question of how all parties could work together to make aviation greener.

Large-scale initiative

The programme is the first large-scale environmental initiative bringing together aviation players on both sides of the Atlantic and was designed to ensure compatibility of the future SESAR and NextGen systems.
After three years, the AIRE initiative has clearly shown what is possible from improved ATM processes and technologies. The results from AIRE are “very promising”, according to the SJU, which released results from the European flight demonstrations performed under AIRE at the ATC Global Show in Amsterdam, the Netherlands, earlier this year.

“The project results show that by improving current procedures, considerable gains in terms of fuel efficiency and consequently lower CO2 emissions can be achieved. Additionally, green approach procedures already enable lower noise pollution and improve local air quality in and around airports,” it says.

AIRE has comprised green flight trials on the ground, in approach and climb as well as in the oceanic domain. In total, six projects were launched – ground movements, green arrivals and departures in Paris; green approaches and climbs at Madrid and Stockholm; and flight optimisation involving Portugal and Iceland.

The AIRE team comprises Adacel, AENA, Aeroports de Paris, Airbus, Air France, AVTECH, DSNA, Egis Avia, Iberia, Icelandair, INECO, Isavia, LFV, Nav Portugal, Novair, TAP Air Portugal, TERN Systems and Thales.

Last year, the partners conducted green ground movement trials at Paris Charles de Gaulle Airport, which demonstrated the effectiveness of a new, collaborative decision support system which minimises taxi time and allows for reduced engine taxi operation.

Green approach procedures, such as continuous descent approach (CDA), and green climb trials were performed at Madrid, Paris and Stockholm airports, while the first required navigation performance (RNP)-based CDA approach ever to be performed in Europe was conducted at Stockholm’s Arlanda Airport. Trials for green oceanic procedures and techniques – speed, horizontal and lateral flight profile optimisation – on selected routes between Europe and North/Central America and the Caribbean were carried out.

The project also involved working with the FAA and US airlines to conduct trials in the oceanic and arrival domains. More than 70 trials on oceanic optimisation and 68 trials aimed at reducing arrival emissions into Miami were conducted.

AIRE activities in 2009 also included the MINT project – an acronym meaning ‘Minimum CO2 in Terminal Manoeuvring Area’. This involved ten demonstration flights, using a Novair Airbus A321at Stockholm’s Arlanda Airport, aimed at investigating how modern aircraft are able to support performance-based operations, resulting in reductions in noise and emissions, and improving predictability in the air transport system.

MINT savings

MINT demonstrated required navigation performance and continuous descent arrival, tapping the greater navigation accuracy derived from the satellite-based Global Positioning System (GPS) and on-board flight management systems. The flights resulted in savings of 145kg of fuel thanks to the optimised vertical descent profile, as well as 20kg of fuel through track-mile savings, resulting in a total CO2 reduction of 518kg, compared with a standard instrument landing system approach.

The MINT project demonstrated that there are capabilities in modern aircraft that can be used to reduce the load placed on the environment by today’s air traffic system, says the SJU.

The main aim of AIRE is to evaluate the applicability and effectiveness of green flight procedures, and it allowed concrete fuel and carbon dioxide savings to be measured. Some 1,152 flights were performed under the AIRE project during 2009. Analysis of the data collected from the flights showed that 400 tonnes of CO2 could be saved – equating to the annual CO2 emissions from 100 passenger cars, according to the SJU.

“The AIRE activities performed in 2009 have shown encouraging results. It is now essential that we transform them from flight trials to day-to-day operations in order to realise the full benefits of SESAR,” says Ky.

This year has seen the operation of gate-to-gate, green transatlantic flights under the programme. On 6 and 7 April, Air France and American Airlines conducted flights using the latest green ATM procedures between Paris Charles de Gaulle and Miami airports. During both flights, enhanced procedures were used to improve the aircraft’s energy efficiency and reduce emissions, from taxiing at Paris Charles de Gaulle to arrival on the parking stand in Miami.

Through the use of shorter taxiing times; continuous ascent; optimum altitude and speed during the cruise phase; and continuous descent at Miami, some 2-3 tons of jet fuel was saved, CO2 emissions were cut by 6-9 tons and noise levels reduced by up to 7dB compared with standard operations. Air France estimates that optimising operations in this way on every long-haul flight to and from North America would reduce CO2 emissions by 135,000 metric tons per year and cut fuel-burn by 43,000 metric tons.

The longer term goal is achievable, the SJU believes. “The SESAR goal of 10 percent savings per flight is still far away, but the AIRE approach, exploiting the full potential of today’s technologies, shows that we will get there. The value of working together with common goals is enormous,” Ky says.

A call for tender to support the expansion of AIRE was recently published and responses are currently being evaluated, says the SJU. Under the tender a number of integrated pre-operational validation projects will be selected, covering surface, terminal, en-route and oceanic domains, or all of them under a gate-to-gate approach. They will be aimed at validating solutions resulting in a reduction of CO2, will be based on present aircraft capabilities and be oriented towards implementation.

Many of the procedures previously demonstrated in AIRE have been transferred to daily operations, while others are expected to be implemented within the next 12 months.

“To accelerate the pace of change we need more AIRE partners working together, in more locations and with a clear focus on transition to day-to-day operations. This is what we are actively working towards as we further expand the programme,” says the SJU.

Asia-Pacific initiative

Not to be left out, the Asia-Pacific region is also playing its part in the form of the Asia and Pacific Initiative to Reduce Emissions (ASPIRE) programme. ASPIRE was launched in February 2008 by Airservices Australia, Airways New Zealand and the FAA, with the aim of accelerating the development and implementation of operational procedures to reduce aviation’s environmental footprint.

Since then, the Japan Civil Aviation Bureau (JCAB) and the Civil Aviation Authority of Singapore (CAAS) have also joined. ASPIRE is now set to welcome a new member, with an application from Aerothai scheduled for consideration at the programme’s annual meeting in Australia in early June.

The ASPIRE partners have always envisioned further expansion of the group across the region. Potential new member air-navigation service providers (ANSPs) undergo a lengthy process to ensure they are capable of becoming a regional leader in emissions reduction, says the group. In particular, the potential partner must show that their service provision is in line with ASPIRE goals by demonstrating their commitment and ability to perform, implement ASPIRE best practices and participate in and support ASPIRE work programmes.

To date, five gate-to-gate green demonstration flights – operated by Air New Zealand, Japan Airlines, Qantas, Singapore Airlines and United Airlines – have been conducted across the Pacific under the ASPIRE project to demonstrate and measure the emission reductions and fuel savings achievable. If Aerothai’s membership is confirmed, it will also be required to lead a demonstration flight.

The demonstration flights used today’s technology and procedures and removed all controllable constraints to demonstrate best environmental efficiency, says the FAA’s DiPasquantonio. All of the flights used procedures including no-delay taxiing, unimpeded climb-out on departure, user preferred routes, dynamic airborne reroute procedures, performance-based navigation separation, reduced vertical separation minima, optimised profile descents and tailored arrivals.

The result was 32,386kg of fuel saved and a 101,986kg reduction in CO2 emissions, according to DiPasquantonio. But ASPIRE is not just about demonstration flights, with the group working to put the tested efficiency procedures into operation on a day-to-day basis.

Outcomes from the demonstration flights feed directly into initiatives, note the partners. One example is the changes identified for dynamic airborne reroute procedures (DARP) processing, after the Qantas Airbus A380 demonstration flight in November 2008. Significant changes to automated controller-pilot datalink communications (CPDLC) message processing within Airservices’ TAAATS air traffic control system were identified, designed and implemented as a result of the flight, says Airservices.

Effective procedures

The ASPIRE partners have identified ten procedures and services that are effective in reducing fuel and emissions in each phase of flight: user-preferred routes (UPR), DARP, oceanic-separation reductions, reduced vertical-separation minima (RVSM), flexible track systems, surface-movement and runway monitoring, departure management, arrivals management, continuous-descent approaches (CDA) and performance-based navigation (PBN).

Progress is being made in the implementation of these procedures in the region. The DARP Enhancement initiative, for example, is working to identify and remove institutional, procedural and technological barriers to the implementation and adoption of DARP in the Asia-Pacific region. DARP offers considerable potential fuel saving, with Air New Zealand estimating, for example, that it could save fuel on 58 percent of its flights from Auckland to North America at an average saving of 453kg per flight. As a result, ASPIRE partners are promoting DARP as a standard service offering.

The ASPIRE partners are also working to remove constraints to UPR expansion in the region. UPRs are currently available in the oceanic region on flights between North America and Australasia for FANS-equipped aircraft. Airservices is expanding UPR availability throughout its flight information region (FIR) and hopes to have it throughout the FIR by mid-2011. ASPIRE partners are examining how UPRs can be made available for flights between Japan and Singapore in particular, and elsewhere in the Pacific.

ASPIRE partners are also focusing on the implementation of oceanic and remote in-trail procedures (ITP), initially in the South Pacific with operational trials planned to start at the end of this year. Operational trials are also being planned for oceanic Automatic Dependent Surveillance – Contract (ADS-C) climb-descent procedures (CDP) in the South Pacific from November. The partners are also assessing whether it is feasible to reduce oceanic separation below the current 30nm lateral and 30nm longitudinal minima.

Making arrivals optimisation part of standard operating procedures is a key initiative of ASPIRE. A number of airports, including Osaka’s Kansai, Melbourne’s Tullamarine and San Francisco International Airport, now allow optimised profile descents on a trial basis. Tailored arrivals into San Francisco, for example, are yielding 617kg of fuel savings per flight.

Auckland Airport is looking to standardise optimised profile descents in 2011, while the CAAS has completed an operational trial with Singapore Airlines at Changi Airport and is planning to expand the trial to other operators. Airservices now has RNP-based arrivals optimisation trials at 17 airports.

Optimising departures

Initiatives are also ongoing to optimise departures. An auto-release procedure is being used at Melbourne, Sydney and Brisbane, for example, whereby tower controllers clear aircraft for take-off without time-consuming voice communications with terminal area controllers. And in New Zealand, trajectories are optimised for individual flights, allowing uninterrupted climb when possible. The FAA is also developing a tool to improve climb efficiency, while Japan’s JCAB is developing a departure optimisation programme.

The ASPIRE partners are also promoting reduced horizontal separation, through the implementation of RNP10 and RNP4 performance-based separation standards in the South China Sea and the bay of Bengal. The group is also working with Vietnam and Indonesia to implement ADS-B in the South China Sea. ADS-B is seen as a tool to achieve emissions reductions through more efficient routing, while also increasing safety.

The ASPIRE partners are developing baseline metrics in order to be able to measure post-implementation benefits of any new technologies and procedures. They also plan to foster “a network of green routes” throughout the Asia-Pacific region under their star-rated city-pair initiative.

Under this concept, higher star ratings will be given to city pairs that have more optimised practices, procedures and services. For example, a route with RVSM and 30nm/30nm separation will have two stars, while one with those plus DARP and UPR available would be an ASPIRE four-star route. Airlines will be encouraged to document and publicise their use of ASPIRE star routes, providing motivation to ANSPs to increase their availability and push for the expansion of best-practice procedures and services throughout the region.

Airservices Australia has been so pleased with the success of the ASPIRE partnership that it is now looking to expand the model into other regions, with the Australian ANSP spearheading the new Indian Ocean Strategic Partnership to Reduce Emissions (INSPIRE).

While ASPIRE focuses on the South Pacific, North Pacific and South East Asia, INSPIRE is aimed at supporting operations in three distinct regions – Arabian Gulf-Australia, Southern Africa-Australia/South East Asia and the South West Indian Ocean-Arabian Gulf. The project has similar aims to ASPIRE, including speeding up the development and implementation of procedures to reduce the environmental footprint for all phases of flight.

To date, a draft strategic plan has been formulated and initial partners Airservices, Airports Authority of India (AAI), South Africa’s Air Traffic and Navigation Services (ATNS), the United Arab Emirates General Civil Aviation Authority and Oman’s Directorate General of Meteorology and Air Navigation are on board.

INSPIRE schedule

Airservices is aiming for an “informal commitment signed off” by late July, to be followed by a formal signing and finalisation of the group’s strategy and work programme. The strategic plan will include recommended ANSP best practices in the Indian Ocean, a regional-works programme and the development of fuel and emissions metrics and reporting for the region.

As with ASPIRE, INSPIRE will include flights demonstrating the fuel and emissions savings possible from using efficiency procedures, including the potential for simultaneous flights. Key players from an airline perspective at this stage are Emirates and Etihad, both of which are “very enthusiastic”, according to Airservices, while AAI and ATNS are yet to confirm their preferred airline partner.

Airservices says it will look to expand the group further with additional ANSPs and airlines after 12 months.

In the wake of ASPIRE and INSPIRE comes a new project – Transpire – which is set to be launched in June. Transpire is part of the Civil Air Navigation Services Organisation (CANSO) Waypoint 2013 programme, which is due to be ratified by its members at their annual general meeting in June.

The project is an attempt to combine and harmonise existing and new ATM initiatives and to develop a more consistent methodology for measuring and reporting progress, rather than the fragmented, disconnected approach used today by ANSPs, says director general Graham Lake. The project will seek to identify areas of airspace inefficiency and will develop a plan to address these inefficiencies.

The initiative is expected to kick off in the Asia-Pacific region in late 2010, with an inter-regional “phase-of-flight best-practices” seminar which will identify functional solutions to address inefficiencies.

Transpire comes in recognition of the fact that many CANSO members are involved in initiatives to improve airspace efficiency, but co-ordinated work and particularly cross-industry collaboration is required to ensure their effectiveness. Tim Rees, CANSO’s environment manager, told the recent ICAO Colloquium the Waypoint 2013 strategy will drive operational and environmental benefits, with Transpire being the showpiece.

“Transpire, through a cross-regional approach, will promote improved operational performance with a focus on the standardised application of proven ATC capability,” says Rees. The project “will promote solutions to problem areas identified by organisations such as IATA and ACI, solutions with global interoperability, and solutions with measurable benefits in the environment, safety and operations. CANSO members will provide dedicated CANSO Captains who will be seconded to CANSO to work with specific regions on specific local issues.”

Increasing efficiency

CANSO says its key goal is for ATM to increase airspace efficiency by 4-5 percent by 2050 – an enormous task when air traffic is forecast to grow by a factor of four, Rees acknowledges. The organisation believes that today’s airspace is about 92 percent efficient, although there are considerable regional variations.

Some 4 percent additional efficiency has been gained since 1999, according to CANSO, through measures including RVSM, air-traffic flow management, collaborative decision making and continuous-descent operations.

“CANSO estimates that some 4 percent efficiency still remains to be achieved by 2050 and the final 4 percent may be unachievable, due to the many trade-offs and interdependencies in our global aviation system,” Rees adds.

Asian Aviation at a glance