When remote tower operations are carried out, ATC services are no longer provided from a regular ATC control tower, but from a remote location that potentially could be very far away from the airport. Such an operation requires different kinds of sensors, information flows and systems, such as video images, radar, flight plan information and radio-telephony.
As part of Single European Sky ATM Research (SESAR) activities, NLR and their consortium partner Air Traffic Control the Netherlands (LVNL) successfully completed a series of live trials and simulation exercises using the NLR ATC Research Simulator (NARSIM) in a special configuration for the LVNL Remote Tower Centre (RTC) located at the LVNL premises at Schiphol. The NARSIM set-up showed the same 360-degree panoramic outside view in a 180-degree monitor arrangement that a Saab camera system provided for Groningen Airport Eelde (GAE), including the special RTC functionality of a Pan-Tilt-Zoom (PTZ) camera. This camera covered a much wider area of the airport and allowed zooming in on pre-defined positions or selected aircraft. The NARSIM set-up was used to familiarize controllers with the specifics of the GAE working environment that was set up in the Schiphol RTC. NARSIM was also used to develop suitable traffic scenarios for simultaneous simulation of a Maastricht-Aachen Airport (MAA) working environment in the RTC.
In September 2016 live trials were eventually carried out with the Saab camera system on top of the control tower at GAE. The Schiphol RTC had full control of the traffic at GAE for almost two hours with a movement rate of more than 30 aircraft per hour. During the remote live trials, a second working environment for MAA was activated on NARSIM, so that tasks on a second airport could be carried out while still controlling GAE remotely. For the MAA environment, a second row of monitors was available on top of the monitors showing the GAE outside panoramic view and a second set of information screens for radar, weather and flight planning were integrated into the controller working positions, as was a second paper flight strip bay and radio-telephony system.
The trials showed that the RTC set-up for GAE was surprisingly workable for the controllers, also in the multiple remote tower set-up with concurrent simulation of the MAA environment by NARSIM, despite the fact that some of the GAE equipment was not considered state-of-the-art leading to reduced handling capabilities for VFR flights and that the location of the camera mast was not optimally chosen. Several questions remain unanswered, such as the actual workload limit that would prohibit carrying out both activities (control of arrival and departure activities at GAE and MAA) in parallel. Another topic for future research would be improved task allocation between the controller and the control tower assistant.
The trials were part of the Remote Tower Large Scale Demonstration project, which is co-funded by the SESAR Joint Undertaking, and consists of several activities aimed at demonstrating the provision of air traffic control (ATC) tower services from a distant, remote location. Partners in the mentioned activity were Swedish Air Navigation Service Provider (ANSP) LFV and German ANSP DFS who both carried out their own trials. Similar activities were also performed in Dublin by IAA, in Milan by ENAV, and in Budapest by HungaroControl.
Future activities are currently being prepared as part of the SESAR-2020 programme. NLR in collaboration with LFV (COOPANS) and Saab will carry out research activities looking at abovementioned workload limits for remote control of multiple airports, as well as procedures for delegating control of an airport to a different working station. Another topic will be planning concepts for the short and the long term to prevent concurrent actions on airports, to reduce the probability of high controller workload, and to optimally plan the resources available at an RTC.
It is expected that such research will be valuable for medium and small-sized airports in the Netherlands that are in need of a more safe and efficient environment for handling the future traffic without undue increase of ATC costs. Such costs would be reduced by creating an RTC being responsible for several airports in the Netherlands and having the right ATC resources available when needed.