ESA launches new programme for Air Traffic Management via satellite

The Single European Sky legislation launched by the European Commission in March 2004 has set the political framework for actions in Europe to unlock viable growth in air transport.

To support this, the Single European Sky Air traffic management Research (SESAR) programme is the 'operational' part, proposing a new approach to reform the air traffic management structure in Europe. It addresses administrative, operational and technical concepts for communication, navigation and surveillance for air traffic safety. Within this wide scope, it provides an opportunity for the satellite industry to demonstrate the efficiency and potential of satellite communications for safety-of-life communications.

While satellite communications have been used on aircraft for many years, so far they have mostly addressed non-safety-critical communications, such as passenger telephone calls and internet connectivity. ESA, with the support of the European space industry, Eurocontrol, air navigation service providers, and national space agencies, is preparing to carry out all the necessary work for satellite communications to be considered under the SESAR programme.

Together with the European Union, these organisations have worked towards implementing a new air traffic management concept. By 2020 global air travel is expected to double, resulting in increasing congestion on the ground and in the air, resulting in a requirement for a new, independent air-to-ground link for aircraft communications. All levels of civil aviation authorities, including Eurocontrol, the agency responsible for European airspace, recognise the need to complement the current systems with added capacity.

Satellite answers the challenge
The European Commission has already set targets for such a system. To reduce delays, and to take into account future demand, the system must be able to handle a three-fold increase in capacity. Safety, too, must be improved by a factor of ten while reducing the burden on the environment by at least ten percent. The final EC requirement is that air traffic management services be 50% less expensive than current systems.

Satellite is an ideal solution for reaching these targets. Satellites can not only deploy additional capacity over vast areas rapidly but also tailor it to regional requirements. By interacting seamlessly between continental, oceanic and polar routes, satellites offer a unique opportunity for safety improvements and the provision of additional services to crews. This is especially important as air traffic communications are currently not seamless, even over the Mediterranean Sea. Furthermore, oceanic routes are still served by the High Frequency (HF) band. The data limitations associated with HF radio communications allow only the most basic forms of communication between pilot and ground. Added to these problems, various countries currently operate different systems, placing another burden on aircraft systems.

A satellite system would provide a much more homogenous solution and could act as a complement to a terrestrial network or, instead, as the primary system in some areas. When coupled with navigation systems like Galileo, satellite communications can even contribute to optimising aircraft trajectories. Future aircraft avionics could be integrated and standardised, improving on safety while at the same time reducing costs.

Iris: Linking the sky to the Earth
Making this a reality will require a new programme line in ESA's Telecommunications Department. ESA Telecom uses the ARTES (Advanced Research in Telecommunications Systems) programme to offer support to European industry in developing ideas for the market and citizenry. The new element for air traffic management via satellite will be ARTES 10. It will be named Iris, after the Greek mythological personification of the rainbow and messenger of the gods, responsible for linking the sky with the Earth. The Iris programme will be divided into three phases.

The first phase will lead up to the 2008 ESA Council meeting at ministerial level, and contribute to early development of the required satellite system and the new communication system in line with pre-agreed planning. The second phase, if approved by the ministers in 2008, will start in mid-2009 and include the system development.

Phase three is planned to start in 2012 and, if approved by the Council at ministerial level in 2011, will support in-orbit verification and certification of the pre-operational system, technical support to deployment of the full system, and preliminary work leading to an enhanced future role for satellites.

Progress to date
In 2002, ESA signed a co-operation agreement with Eurocontrol on the deployment of space technology in civil aviation. Additionally ESA has participated in a number of international forums where regulatory matters and technical standards are addressed.

In order to demonstrate the technical feasibility of a dedicated satellite based system, several ESA funded studies have been carried out for Satellite Data Link System (SDLS). The latest study had involved a laboratory demonstrator that proved the feasibility of a satellite based ATM system. The demonstration had used L-band capacity on the ARTEMIS satellite.

Currently, ESA and CNES, with an industrial consortium under the guidance of Eurocontrol are carrying out a study called 'Satcom for ATM: building a Business Case'. Expected to be completed this year, this year long study is focusing on demonstrating the economic benefits of deploying a new, satellite based system. The business case will rely on the successful conclusions drawn from the technical SDLS study.

"ARTES 10 is an example of a standard institutional project where ESA's support is fundamental in bringing relevant actors together." explains Ms Nathalie Ricard, of the Telecommunications and Navigation Directorate of the European Space Agency. "Our support is needed because the return on investment would not occur until 2020 and because the user community is not yet fully familiar with the advantages that satellite can bring to ATM. The end result will bring benefits to the fast growing air transport industry."

The envisaged system
ATM via satellite will offer many benefits to users. Cockpit crews will be able to communicate seamlessly when travelling from airspaces over land to ocean airspaces. Airlines could communicate directly with their airborne crews across any geographical are equipped with such a system. Air traffic controllers would better guide aircraft through the skies, avoiding storms and enabling optimal routing, saving on fuel and flight time, hence reducing pollution and benefiting the environment.

Satellites can provide global coverage, and contribute to several regional systems. A regional ATM satellite system covering a particular geographical area, in this case Europe, would be designed to possess redundancy an thus improve safety. The space segment would consist of at least two payloads aboard separate satellites, which would provide the link from feeder stations to mobile users, in this case aircraft.

On the ground, a Network Management Stations with a second acting as a back-up would be required. Complimentary Ground Earth Stations (GES) would complete the ground segment. Information would be forwarded to satellites from these Ground Stations.

all images ESA