Eleven airlines are taking part in trials of equipment that will enable air traffic control surveillance in non-radar airspace.

Imminent in-service trials of automatic dependent surveillance - broadcast (ADS-B) equipment in a fleet of more than 200 commercial airliners is expected to earn European Aviation Safety Agency certification for the on-board installations by the end of the year, according to Eurocontrol, which is co-ordinating the operation.

It will also enable air navigation service providers (ANSP) in both radar-covered and non-radar areas to test their ADS-B ground stations and prepare procedures for using ADS-B for aircraft surveillance, says Eurocontrol.

The participating airlines have modified their aircraft to take part in the trials which, when the equipment is certificated, will enable them to receive radar-like ATC service in areas - like the Mediterranean and some provincial airport terminal areas - where radar is not provided.

Where radar cover exists, ADS-B provides an accurate back-up surveillance system with a much faster update rate than radar, Eurocontrol points out. It expects "ADS-B out" - the ground systems - to be operational in continental European airspace next year.

The airlines equipped with "ADS-B in" - the on-board systems - that are taking part in the trials and certification include Aegean Airways, Air Europa, Airbus Transport International, British Airways, CCM Airlines, Cyprus Airways, Hapagfly, Lufthansa, Niki, Ryanair and Scandinavian Airlines.

Eurocontrol's manager of its Cascade programme, which includes the ADS-B trials as well as the implementation of other forms of datalinking services, says: "The response to our call [to the airlines] for interest exceeded our expectations. It shows that airlines are willing to invest if the objectives and the benefits are clear."

ADS-B will also provide pilots with traffic situational awareness displays with greater clarity and accuracy than airborne collision avoidance systems can give (Flight International, 23-29 January).

Meanwhile, Eurocontrol's programme to deal with the increasingly serious shortage of secondary surveillance radar (SSR) transponder "squawk" codes is also being prepared for implementation in 2008.

Known as the centralised SSR code assignment and management system (CCAMS), the idea is to make more efficient use of the available 4,096 codes by abandoning the inefficient system of allocating batches of specific codes to nations.

Instead, individual codes would be allocated via a central server at Eurocontrol's Central Flow Management Unit to each flight as its flight plan is activated.

Source: Flight International