Satellite Communication for Air Traffic Management (Iris) Overview

 

The ARTES Satellite Communication for Air Traffic Management element, or Iris, is the European Space Agency programme to support the development of a satellite-based communication system for European air traffic management (ATM).
The Iris Programme is a new type of initiative for ESA, where the space component is one of the component in a much larger system, tuned to the needs of external partners and end-users who are not always familiar with satellite technology. Because of this, a long-term, incremental approach is necessary.
 
Iris will complement existing and planned systems, supporting the growth of worldwide air traffic. It is anticipated that Iris will be fully operational in 2028, with deployment of a precursor service foreseen for 2018.
 
Iris will enable 4D trajectory management via satellite, for both continental and oceanic airspaces, as a safe and reliable service. Communications will take place via robust data links and will ultimately be used by the vast majority of aircraft, complemented with conventional voice communications between pilots and controllers. To achieve this goal, Iris will also develop and validate a new standard for satellite communications that can be used for ATM in any region of the world.
 
Iris is part of a much broader push to modernise how air traffic is managed in close collaboration with the SESAR Joint Undertaking launched in 2006 by EUROCONTROL and the European Union. The new communication system will be standardised by the European Organisation for Civil Aviation Equipment (EUROCAE) and the International Civil Aviation Organisation (ICAO).

What is SESAR?

In recognising the need to modernise Europe's ATM, the European Commission  initiated the Single European Sky Policy. Part of the policy includes its technological pillar – the Single European Sky ATM Research Programme (SESAR). SESAR Programme aims to develop a high-performance ATM system to enable the safe and environmentally-friendly development of air transport. SESAR Programme is defining and evaluating two different communication technologies that will be used in parallel for this system. A new terrestrial data link, with antennas on-ground, and a satellite-based service. This multi-link will offer the safety and capacity requirements for tomorrow's ATM systems. ESA launched the Iris Programme in 2007 to develop and validate the satellite component.

What is EUROCONTROL?

EUROCONTROL is an international organisation founded in 1960 and composed of Member States from the European Region, including the European Community which became a member in 2002. It is involved in almost every aspect of European air traffic management.

What is the International Civil Aviation Organisation?

The International Civil Aviation Organization is an agency of the United Nations. It codifies the principles and techniques of international air navigation and fosters the planning and development of international air transport to ensure safe and orderly growth.

Why is satellite-based air traffic management needed?

Air traffic is currently managed by a decades-old VHF radio system in which all communications between air traffic control personnel and pilots are in spoken form. While the system works well, it has its limitations, particularly in dense areas with heavy airline traffic, such as Europe. With over 40,000 daily flights a day predicted for 2020, the European ATM system will not be able to cope with this volume of traffic in an efficient manner. Moreover, European ATM is highly fragmented. It consists of more than sixty sectors, all managed individually. This reduces efficiency and adds to the cost of flying.

What are the challenges?

Because the aviation world operates on a global basis, any new ATM solution must be supported and coordinated worldwide. Change will take time as manufacturing schedules for aircraft are set years in advance. It must be done incrementally, allowing existing fleets to be retrofitted with the new system in an economically viable way. Given the narrow profit margins in the airline business, costs will have to be kept to a minimum.
 
Airlines have accepted the need to switch to digital and indeed some satellite services are already in use.
 
For aircraft, user terminals will need to be low cost, with small antennas and low-power requirements in the aircraft. The satellite system infrastructure will need to be modular so it can be deployed worldwide with interoperable services from various service providers.

What are the benefits?

Aircraft in European airspace fly an extra 42 km on average to meet safety regulations, incurring unnecessary costs and CO2 emissions. Four-dimensional (4D) trajectories of aircraft via data links between the aircraft and the ground will enable precise tracking of aircraft and therefore more efficient management of flight paths, with fewer flight cancellations and delays.
 
A key benefit of automated tracking is managing unexpected situations. Should an aircraft have to suddenly change course because of weather conditions or in an emergency, it could do so in real time and without risk, resulting in safer air travel.
While satellite communications on board aircraft have been used for passenger communications for many years, they are not allowed as a primary means of safety communications. What is fundamentally new with the concept developed by SESAR is that it uses satellite communications as an integral part of the new European ATM system in most phases of flights. Aircraft will be able to communicate while en route at cruising altitude, but also during take-off and landing, and while manoeuvring close to airports. This is fundamentally different from today's use of satellite communications and was – until now – not compatible with existing technology.
 
Through the planned improvements, SESAR has an objective to save between 8 and 14 minutes per flight, as well as, up to 500 kg of fuel and up to 1575 kg of CO2 on average. SESAR plans also to reduce ATM-related costs by half.
 
Having defined the ATM communication standard and being the first deploying these new safety services, the European satellite industry will be best placed to develop new opportunities and export to other world regions.

What is ESA's contribution?

ESA's objective is to help aviation authorities to deploy a global service supplied by multiple parties. ESA activities belong to the satellite technology domain; the SESAR Joint Undertaking will then use this technology for the operational service verification, before the final deployment.
 
Modernisation on this scale demands a long-term stepped approach. To be coherent in content and time with the SESAR programme, the Iris Programme proposes the development of the aeronautical safety of life satellite communication technology, in a stepwise approach characterized by increasing levels of performance.

Iris Precursor, the first stage, is based on Inmarsat's SwiftBroadband Safety. It will be  a key milestone in modernizing the air traffic management and ultimately making data links the primary means of communication. Iris Precursor will provide the technologies in support to short-to-medium term ATM air–ground communications service enabling initial 4D flight path control. While the initial focus will be on Europe, the capabilities developed will open opportunities for deployment in North America and other regions where the growth of air traffic is placing strain on ground-based VHF networks. The required updates of the SwiftBroadband network to meet the stringent performance and safety requirement of the target services were identified thanks to preparatory study THAUMAS.

Iris Long-Term, the second stage, will result in the full implementation of the Iris system, meeting the ultimate communication needs of future ATM services.

Iris Long-Term will take into account the lessons learned from ANTARES and will be based on the evolution of Iris Precursor to guarantee continuity in the technical service provision. Iris Long-Term will offer global interoperability based on a global communications standard. This standard, today drafted in ANTARES, will ensure that aircraft equipped with a standard terminal will be able to communicate anywhere via compatible satellite systems.

Iris Long-Term also encompasses the development of dedicated technology enabling applications implementing multilink functionality jointly with other new terrestrial data-links. In practice, the system will be transparent to the pilot and the controller; flight crew will send and receive information to and from flight management facilities seamlessly.

The system will be designed to ensure low costs both for equipping the aircraft and for the on-going service of handling communications.

What is the current status of Iris?

The ESA–Inmarsat collaboration for Iris was established following a major funding commitment approved at ESA’s 2012 Council at Ministerial Level in Italy. An initial set of satcom services was designed and developed under the Iris Precursor contract signed with Inmarsat as prime contractor in November 2014. 

The next stage of the partnership, Iris Service Evolution, will identify the technical, commercial and operational requirements of the satcoms part of the Single European Sky ATM Research programme.

The Iris programme’s first airline partner is Alitalia, the national carrier of Italy. Additional participants include a consortium of over thirty companies, among which are Airbus, Boeing, NATS and Thales Alenia Space.