A Scandinavian Airlines Boeing 737 has completed the first live test of an anti-runway incursion service in a trial at Stockholm Arlanda airport.

The test, involving one of SAS's 737-600s, took place on 29 September. The system has in-cockpit displays that show the own-ship position and the positions of all the other aircraft and vehicles in the area using VHF datalink mode four (VDL M4) to ensure all pilots, drivers and the control tower are informed of each other's movements.

The VDL M4 is part of the automatic dependent surveillance - broadcast (ADS-B) system. The live tests followed simulations carried out in 2004 and 2005 on what could be achieved.

The work is part of the European Union's North European ADS-B network Update Project (NUP)2+, which is the extended second phase of NUP. Its partners include Swedish air navigation service provider, LFV, Stockholm Arlanda airport, SAS Sweden, Saab Security Systems and Rockwell Collins.

"The backbone of the system is the shared information through ADS-B. Now finally all the [taxiway vehicle operators] have the same information at the same time," says NUP2+ project member and former SAS pilot, Per Ahl.

He adds that the system has different alerts for different vehicles when they are in the various zones around the airport. Vehicle drivers and the tower receive an alert if there is an incoming aircraft. Then at 15s before the runway threshhold an alert warns of an incoming aircraft that has to be resolved and at 8s to threshold the pilot receives an alert to go around.

The work at Arlanda has also tested a service called Taxi Route or voiceless Taxi. This uses the aforementioned display with visible hold points along the route from push back to the runway. The tower is alerted if an aircraft deviates from its path by more than 35m (115ft), and Ahl says that more tests will follow including during real operations.

Source: FlightGlobal.com