The Netherlands Aerospace Centre (NLR) has checked and validated a guidance concept in its air traffic control simulator NLR ATC Research Simulator (NARSIM).

During the testing of the so-called ‘Virtual Stop Bar Guidance Concept’, the researchers at NLR made several changes to the working position for the traffic controller in the tower to allow the status of a virtual ‘stop bar’ to be displayed for each aircraft selected on the radar screen.

Stop bars work like traffic lights at the airport, indicating whether aircraft can proceed taxiing or if they need to stop.

Digital cease bars do not exist as physical objects on taxiways or on the platform and are only shown on the displays of air traffic controllers or pilots.

Moreover, the new working concept enables air traffic controllers to select the taxi route to a virtual stop bar for each aircraft.

“Pilots can view the correct route to the position of the virtual stop bar on their navigation screen.”

Data is exchanged between the control tower and pilots through data communication. The so-called data link, which ensures that the status of a virtual stop bar, as well as the route to the virtual stop bar, are shown on the navigation display in the cockpit.

NLR said that the new technology will enable more aircraft to use the available space on the platform and taxiways simultaneously during low visibility conditions.

Practically, the new technology will allow aircraft to keep moving, thereby increasing the capacity of the taxiways. An additional benefit is that the pilots can view the correct route to the position of the virtual stop bar on their navigation screen.

NLR, in collaboration with Italian air traffic controllers, developed the concept and the ground control displays.

A touch-pen display was used to integrate radar information, the switching of stop bars, the assignment of clearance limits and the route, and other relevant flight information.

The real-time simulation trial with air traffic controllers and pilots, as well as the validation of the new technology, were carried out on NARSIM.