The air traffic controller sits at his workstation during the simulation in the Apron and Tower Simulator (ATS), as he would in reality, and is able to control the aircraft as per real-life operational procedures as well as coordinate operational sequences.
The new taxiway is tested in both winter and summer conditions. Air traffic controllers have to tackle various scenarios – from scheduled air traffic to complex exceptional cases. Whether there is a defect in the aircraft landing gear or an aborted take-off, all scenarios are analysed by the DLR team and discussed with controllers in order to compile suggestions for improvement.
New guidance system to avoid frequent crossings on the runway at Zurich airport
Air traffic controllers from Zurich are testing planned 'rerouting' in an intensive simulation at DLR
Various operational procedures for the most diverse traffic and weather conditions are run through and their efficiency analysed
Zurich airport is divided into two sections by an active runway. This centrally located runway has to be crossed by most of the arriving and departing aircraft. With the 'Rerouting runway 28' project, aircraft will use a new taxiway east of the runway, thereby considerably reducing the number of crossings to further increase safety. But can this new taxiway be operated smoothly? And how can operational procedures be optimised to the fullest extent? To investigate these questions, Zurich airport commissioned the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) to carry out a feasibility study. As part of the study, air traffic controllers from Zurich virtually tested the new taxiway in November and December 2016 at DLR.
Testing the airports of tomorrow, today
The investigations are made possible by the Apron and Tower Simulator (ATS) at the DLR Institute of Flight Guidance in Braunschweig, which is part of the Air Traffic Validation Center. At the Institute, the structure of tomorrow's airports can be visualised today. During the simulation, the controller sits at the workstation – as in real work conditions – and is able to guide the aircraft according to real-life operational procedures and coordinate operational sequences.
"In the feasibility study, we provided the Zurich tower and apron controllers with a realistic simulation of the new taxiway situation that was as close to reality as possible, thereby enabling them to experience the resulting changes in the airport's surface traffic management," says Ronny Scharf, project manager from Zurich airport. "The focus here was on aspects such as the greater scope of responsibility and adapting taxiing instructions in the most manageable way possible, as well as the question regarding how exceptional operational situations can be handled in the new apron layout."
Controllers and simulation pilots
In the ATS, high-resolution projectors and screens are used to virtually display the airport. The controllers issue air traffic control clearances using a simulated radio system. Their commands are then carried out by so-called 'simulation pilots'. These DLR employees conduct radio communication like real pilots and can thereby control multiple virtual aircraft simultaneously using simplified procedures. DLR is therefore able to test the new taxiway for Zurich airport under the most diverse traffic and weather conditions.
"In addition to a set-up that is as true to reality as possible, our entire team also gives great importance to a comprehensive investigation," explains DLR researcher Schier from the DLR Institute of Flight Guidance, who is responsible for ATS activities. Alongside simulation pilots, psychologists, simulation experts and aviation experts are supporting the study. Air traffic controllers' impressions on the new system, workload and situational awareness will be analysed alongside aircraft taxi and wait times and the frequency and duration of instructions and clearances given by radio. "Only by incorporating all aspects – from the air traffic controllers' opinions to the number of take-offs and landings – can we ultimately assess what improvements the new taxiway will bring," continues Schier.
One of the largest simulation set-ups in the world
For the Zurich airport study, the ATS is being used in one of its largest expansion levels. Only a few simulators in the world are able to provide the large and complex possibilities required for this study. A total of eight air traffic controllers guide the virtual aircraft and ground vehicles in two separate control rooms. A third room houses 10 simulation pilots, ground vehicle operators and coordinators. They steer the aircraft, drive the aircraft tugs to push the aircraft back and receive telephone calls as airport management coordinators or de-icing coordinators. The entire simulation is controlled by a team of four, consisting of test observers and simulation leaders. The new taxiway is tested using simulations over a period of two weeks with different air traffic controllers – in both winter and summer conditions. The controllers have to tackle various scenarios – from scheduled air traffic to complex exceptional cases. Whether there is a defect in the landing gear or an aborted take-off, all scenarios are analysed by the DLR team and discussed with the controllers in order to compile a list of suggestions for improvement.
"Ultimately, our feasibility study is helping Zurich airport to optimally exploit the full potential of the new taxiway and to find suitable procedures to enable improvements in safety and efficiency in taxiing traffic at Zurich airport to be optimally leveraged," says Schier. The data acquired is to be evaluated by March 2017.
