Europe's air traffic control centres are finally to be linked by a unified modern communications network. This will replace existing links between centres and the central flow management unit and the European Aeronautical Information Service.

Eurocontrol says the contract was signed by the network provider, communications specialist Sita and five of the 38 Eurocontrol member state air navigation service providers (ANSP) at its Brussels headquarters today.

Area control centres are now linked on a bilateral basis to neighbouring centres, usually by an ordinary telephone line. This, says Eurocontrol, is inadequate for the future Single European Sky as set out under the SESAR programme, which envisages a network-centric "neural" system to be known as Swim (system-wide information management).

The Sita system, called Pens (pan-European communications network service), provides a purpose-built, secure, high-capacity internet protocol-based communications network that can carry datalinking and voice messages. Security will be assured by the system's architecture, which consists of a series of virtual private networks, one for each ANSP, that are interlinked for centre-to-centre communication.

The existing bilateral communications system is so primitive that, in July 2002, when controllers at Karlsruhe in Germany could see a traffic conflict developing in neighbouring Swiss-controlled airspace, they could not contact the Zurich centre to warn controllers there, because the line was down.

There was more than 2min to go before a Bashkirian Tu-154M and a DHL Boeing 757 collided. The Zurich controller noticed the conflict too late, and the two airliners collided over Uberlingen, southern Germany destroying both aircraft and killing all on board.

Pens will also replace all the individual IP network services that have been providing connections to the central flow management unit and the European Aeronautical Information Service.

Ian Hall, director of development and investment at UK ANSP NATS, says: "This is a big step as it is the first stage in introducing a Europe-wide information network that meets the needs of SESAR. This contract signals the creation of a common system to simplify the flow of information necessary as we move into a new era of integrated and streamlined air traffic management."

NATS says that it has been chairing the Pens development focus group, comprising Eurocontrol and the ANSPs, planning and procuring for the project for the last three years, and comments: "Negotiations have been extensive because of the complex interfaces between each provider for each national air traffic operation, all on different networks."

Source: Flight International